Document Outline
- FEATURES
- APPLICATIONS
- GENERAL DESCRIPTION
- FUNCTIONAL BLOCK DIAGRAM
-
-
-
-
-
-
-
-
- ANALOG INTERFACE INPUTS
- POWER SUPPLY BYPASSING
- PLL
- OUTPUTS (BOTH DATA AND CLOCKS)
- DIGITAL INPUTS
-
Analog/HDMI
Dual Display Interface
AD9880
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
2005 Analog Devices, Inc. All rights reserved.
FEATURES
Analog/HDMI dual interface
Supports high bandwidth digital content protection
RGB-to-YCbCr 2-way color conversion
Automated clamping level adjustment
1.8 V/3.3 V power supply
100-lead LQFP Pb-free package
RGB and YCbCr output formats
Analog interface
8-bit triple ADC
100 MSPS maximum conversion rate
Macrovision detection
2:1 input mux
Full sync processing
Sync detect for hot plugging
Midscale clamping
Digital video interface
HDMI v 1.1, DVI v 1.0
150 MHz HDMI receiver
Supports high bandwidth digital content protection
(HDCP 1.1)
Digital audio interface
HDMI 1.1-compatible audio interface
S/PDIF (IEC90658-compatible) digital audio output
Multichannel I2S audio output (up to 8 channels)
APPLICATIONS
Advanced TV
HDTV
Projectors
LCD monitor
GENERAL DESCRIPTION
The AD9880 offers designers the flexibility of an analog interface
and high definition multimedia interface (HDMI) receiver inte-
grated on a single chip. Also included is support for high band-
width digital content protection (HDCP).
Analog Interface
The AD9880 is a complete 8-bit 150 MSPS monolithic analog inter-
face optimized for capturing component video (YPbPr) and RGB
graphics signals. Its 150 MSPS encode rate capability and full power
analog bandwidth of 330 MHz supports all HDTV formats (up to
1080 p) and FPD resolutions up to SXGA (1280 1024 @ 75 Hz).
The analog interface includes a 150 MHz triple ADC with internal
1.25 V reference, a phase-locked loop (PLL), and programmable
gain, offset, and clamp control. The user provides only 1.8 V and
3.3 V power supplies, analog input, and Hsync. Three-state
FUNCTIONAL BLOCK DIAGRAM
DATACK
DE
V
SYNC
SYNC
PROCESSING
AND
CLOCK
GENERATION
DATACK
2
REF
HSOUT
VSOUT
SOGOUT
HDMI RECEIVER
DIGITAL INTERFACE
REFOUT
REFIN
CLAMP
A/D
2:1
MUX
2:1
MUX
2:1
MUX
2:1
MUX
SPDIF OUT
8-CHANNEL
I
2
S OUT
2
MCLK
LRCLK
HDCP
2
DATACK
HSOUT
VSOUT
SOGOUT
DE
M
U
XES
RG
B
Y
Cb
Cr M
AT
RIX
R/G/B 8X3
OR YCbCr
R/G/B 8X3
or YCbCr
YCbCr (4:2:2
OR 4:4:4)
AD9880
R/G/B OR YPbPr
IN0
R/G/B OR YPbPr
IN1
HSYNC 0
HSYNC 1
HSYNC 0
HSYNC 1
SOGIN 0
SOGIN 1
COAST
CKINV
CKEXT
FILT
SCL
SDA
RX1+
RX1
RX2+
RX2
RXC+
RXC
R
TERM
MCL
MDA
DDCSCL
DDCSDA
RX0+
RX0
H
SYNC
R/G/B 8X3
SERIAL REGISTER
AND
POWER MANAGEMENT
ANALOG INTERFACE
05087-001
SCLK
4
Figure 1.
CMOS outputs can be powered from 1.8 V to 3.3 V. The
AD9880's on-chip PLL generates a pixel clock from Hsync. Pixel
clock output frequencies range from 12 MHz to 150 MHz. PLL
clock jitter is typically less than 700 ps p-p at 150 MHz. The
AD9880 also offers full sync processing for composite sync and
sync-on-green (SOG) applications.
Digital Interface
The AD9880 contains a HDMI 1.1-compatible receiver and sup-
ports all HDTV formats (up to 1080 p and 720 p) and display
resolutions up to SXGA (1280 1024 @75 Hz). The receiver
features an intrapair skew tolerance of up to one full clock cycle.
With the inclusion of HDCP, displays can now receive encrypted
video content. The AD9880 allows for authentication of a video
receiver, decryption of encoded data at the receiver, and renewa-
bility of the authentication during transmission, as specified by the
HDCP v 1.1 protocol.
Fabricated in an advanced CMOS process, the AD9880 is provided
in a space-saving, 100-lead LQFP surface-mount Pb-free plastic
package and is specified over the 0C to 70C temperature range.
AD9880
Rev. 0 | Page 2 of 64
TABLE OF CONTENTS
Specifications..................................................................................... 3
Analog Interface Electrical Characteristics............................... 3
Digital Interface Electrical Characteristics ............................... 4
Absolute Maximum Ratings............................................................ 6
Explanation of Test Levels ........................................................... 6
ESD Caution.................................................................................. 6
Pin Configuration and Function Descriptions............................. 7
Design Guide................................................................................... 12
General Description................................................................... 12
Digital Inputs .............................................................................. 12
Analog Input Signal Handling.................................................. 12
Hsync and Vsync Inputs............................................................ 12
Serial Control Port ..................................................................... 12
Output Signal Handling............................................................. 12
Clamping ..................................................................................... 12
Timing.......................................................................................... 16
HDMI Receiver........................................................................... 20
DE Generator .............................................................................. 20
4:4:4 to 4:2:2 Filter ...................................................................... 20
Audio PLL Setup......................................................................... 21
Audio Board Level Muting........................................................ 21
Timing Diagrams ....................................................................... 21
2-Wire Serial Register Map ........................................................... 23
2-Wire Serial Control Register Detail.......................................... 37
Chip Identification ..................................................................... 37
PLL Divider Control .................................................................. 37
Clock Generator Control .......................................................... 37
Input Gain ................................................................................... 38
Input Offset ................................................................................. 38
Sync .............................................................................................. 39
Coast and Clamp Controls........................................................ 39
Status of Detected Signals ......................................................... 40
Polarity Status ............................................................................. 41
BT656 Generation ...................................................................... 46
Macrovision................................................................................. 48
Color Space Conversion ............................................................ 49
2-Wire Serial Control Port........................................................ 56
PCB Layout Recommendations.................................................... 58
Color Space Converter (CSC) Common Settings...................... 60
Outline Dimensions ....................................................................... 62
Ordering Guide .......................................................................... 62
REVISION HISTORY
8/05--Revision 0: Initial Version
AD9880
Rev. 0 | Page 3 of 64
SPECIFICATIONS
ANALOG INTERFACE ELECTRICAL CHARACTERISTICS
V
DD,
V
D
= 3.3 V, DV
DD
= PV
DD
= 1.8 V, ADC clock = maximum.
Table 1.
AD9880KSTZ-100
AD9880KSTZ-150
Parameter
Temp
Test
Level
Min
Typ Max Min
Typ Max Unit
RESOLUTION
8
8
Bits
DC
ACCURACY
Differential Nonlinearity
25C
I
0.6
+1.6/
1.0
0.7
+1.8/
1.0
LSB
Integral
Nonlinearity
25C
I
1.0 2.1
1.1 2.25 LSB
No Missing Codes
Full
Guaranteed
Guaranteed
ANALOG
INPUT
Input
Voltage
Range
Minimum
Full VI
0.5
0.5
V
pp
Maximum
Full VI
1.0 1.0 V
pp
Gain
Tempco
+25C V
100
220
ppm/C
Input Bias Current
+25C
V
0.2
1
A
Input Full-Scale Matching
25C
Full
VI
VI
1.25
1.50
5
7
1.25
1.50
5
7
%FS
%FS
Offset Adjustment Range
Full
V
50
50
%FS
SWITCHING PERFORMANCE
1
Maximum Conversion Rate
Full
VI
100
150
MSPS
Minimum Conversion Rate
Full
VI
10
10
MSPS
Data to Clock Skew
Full
IV
-0.5
+2.0
-0.5
+2.0
ns
Serial
Port
Timing
t
BUFF
Full VI
4.7 4.7 s
t
STAH
Full VI
4.0 4.0 s
t
DHO
Full VI
0 0 s
t
DAL
Full VI
4.7 4.7 s
t
DAH
Full VI
4.0 4.0 s
t
DSU
Full VI
250 250 ns
t
STASU
Full VI
4.7 4.7 s
t
STOSU
Full VI
4.0 4.0 s
HSYNC Input Frequency
Full
VI
15
110
15
110
KHz
Maximum PLL Clock Rate
Full
VI
100
150
MHz
Minimum PLL Clock Rate
Full
IV
12
12
MHz
PLL Jitter
+25C
IV
700
700
ps p-p
Sampling
Phase
Tempco Full IV
15
15
ps/C
DIGITAL INPUTS: (5V tolerant)
Input Voltage, High (V
IH
)
Full VI
2.6 2.6 V
Input Voltage, Low (V
IL
) Full VI
0.8
0.8
V
Input Current, High (I
IH
) Full
V
-82
-82
A
Input Current, Low (I
IL
)
Full
V
82
82
A
Input
Capacitance
25C V
3
3
pF
DIGITAL
OUTPUTS
Output Voltage, High (V
OH
) Full
VI V
DD
- 0.1
V
DD
- 0.1
V
Output Voltage, Low (V
OL
)
Full VI
0.4
0.4
V
Duty Cycle, DATACK
Full
V
45
50
55
45
50
55
%
Output
Coding
Binary
Binary
POWER
SUPPLY
V
D
Supply
Voltage
Full
IV 3.15 3.3 3.47 3.15 3.3 3.47 V
DV
DD
Supply
Voltage
Full
IV 1.7
1.8 1.9 1.7
1.8 1.9 V
AD9880
Rev. 0 | Page 4 of 64
AD9880KSTZ-100
AD9880KSTZ-150
Parameter
Temp
Test
Level
Min
Typ Max Min
Typ Max Unit
V
DD
Supply
Voltage
Full
IV 1.7
3.3 3.47 1.7
3.3 3.47 V
PV
DD
Supply
Voltage
Full
IV 1.7
1.8 1.9 1.7
1.8 1.9 V
I
D
Supply Current (V
D
) 25C
VI
260
300
330
mA
I
DVDD
Supply Current (DV
DD
) 25C
VI
45 60
85
I
DD
Supply Current (V
DD
)
2
25C VI
37 100
3
130
3
mA
IP
VDD
Supply Current (P
VDD
) 25C
VI
10 15
20
mA
Total Power
Full
VI
1.1
1.4
1.15
1.4
W
Power-Down
Dissipation Full
VI
130
130
mW
DYNAMIC
PERFORMANCE
Analog Bandwidth, Full
Power
25C
V
330
330
MHz
SignaltoNoise Ratio (SNR)
25C
I
46
46
dB
Without
Harmonics
Full
V
45
45
dB
f
IN
= 40.7 MHz
Crosstalk
Full
V
60
60
dBc
THERMAL
CHARACTERISTICS
JA
-Junction-to-Ambient
V
35
35
C/W
1
Drive strength = high.
2
DATACK load = 15 pF, data load = 5 pF.
3
Specified current and power values with a worst case pattern (on/off).
DIGITAL INTERFACE ELECTRICAL CHARACTERISTICS
V
DD
= V
D
=3.3 V, DV
DD
= PV
DD
= 1.8 V, ADC clock = maximum.
Table 2.
AD9880KSTZ-100
AD9880KSTZ-150
Parameter
Test
Level Conditions
Min
Typ
Max Min
Typ
Max Unit
RESOLUTION
8
8
Bit
DC DIGITAL I/O Specifications
High-Level Input Voltage, (V
IH
) VI
2.5
2.5
V
Low-Level Input Voltage, (V
IL
) VI
0.8
0.8
V
High-Level Output Voltage, (V
OH
) VI
V
DD
- 0.1
V
Low-Level Output Voltage, (V
OL
) VI
V
DD
- 0.1
0.1
0.1
V
DC SPECIFICATIONS
Output High Level
IV
Output drive = high
36
36
mA
(I
OHD
) (V
OUT
= V
OH
)
IV
Output drive = low
24
24
mA
Output Low Level
IV
Output drive = high
12
12
mA
I
OLD
, (V
OUT
= V
OL
)
IV
Output drive = low
8
8
mA
DATACK High Level
IV
Output drive = high
40
40
mA
V
OHC
, (V
OUT
= V
OH
)
IV
Output drive = low
20
20
mA
DATACK Low Level
IV
Output drive = high
30
30
mA
V
OLC
, (V
OUT
= V
OL
)
IV
Output drive = low
15
15
mA
Differential Input Voltage, Single Ended
Amplitude
IV
75
700
75
700
mV
AD9880
Rev. 0 | Page 5 of 64
AD9880KSTZ-100
AD9880KSTZ-150
Parameter
Test
Level
Conditions Min
Typ
Max
Min
Typ
Max
Unit
POWER SUPPLY
V
D
Supply Voltage
IV
3.15
3.3
3.47
3.15
3.3
3.47
V
V
DD
Supply
Voltage
IV
1.7
3.3 347 1.7 3.3 347 V
DV
DD
Supply Voltage
IV
1.7
1.8
1.9
1.7
1.8
1.9
V
PV
DD
Supply Voltage
IV
1.7
1.8
1.9
1.7
1.8
1.9
V
I
VD
Supply Current (Typical Pattern)
1
V
80
100
80
110
mA
I
VDD
Supply Current (Typical Pattern)
2
V
40
100
3
55
175*
I
DVDD
Supply Current (Typical Pattern)
1, 4
V
88
110
110
145
mA
I
PVDD
Supply Current (Typical Pattern)
1
V
26
35
30
40
mA
Power-Down Supply Current (I
PD
) VI
130
130
mA
AC SPECIFICATIONS
Intrapair (+ to -) Differential Input Skew
(T
DPS
)
IV
360
pS
Channel to Channel Differential Input
Skew (T
CCS
)
IV
6
Clock
Period
Low-to-High Transition Time for Data and
Controls (D
LHT
)
IV
Output drive = high;
C
L
= 10 pF
900
ps
IV
Output drive = low;
C
L
= 5 pF
1300
ps
Low-to-High Transition Time for
DATACK (D
LHT
)
IV
Output drive = high;
C
L
= 10 pF
650
ps
IV
Output drive = low;
C
L
= 5 pF
1200
ps
High-to-Low Transition Time for Data and
Controls (D
HLT
)
IV
Output drive = high;
C
L
= 10 pF
850
ps
IV
Output drive = low;
C
L
= 5 pF
1250
ps
High-to-Low Transition Time for
DATACK (D
HLT
)
IV
Output drive = high;
C
L
= 10 pF
800
ps
IV
Output drive = low;
C
L
= 5 pF
1200
ps
Clock to Data Skew
5
(T
SKEW
) IV
0.5
2.0
0.5
2.0
ns
Duty Cycle, DATACK
5
IV
45
50
55
%
DATACK Frequency (F
CIP
) VI
20
150
MHz
1
The typical pattern contains a gray scale area, output drive = high. Worst case pattern is alternating black and white pixels.
2
The typical pattern contains a gray scale area, output drive = high.
3
Specified current and power values with a worst case pattern (on/off).
4
DATACK load = 10 pF, data load = 5 pF.
5
Drive strength = high.
AD9880
Rev. 0 | Page 6 of 64
ABSOLUTE MAXIMUM RATINGS
Table 3.
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
EXPLANATION OF TEST LEVELS
Test Level
I.
100% production tested.
II.
100% production tested at 25C and sample tested at
specified temperatures.
III.
Sample tested only.
IV.
Parameter is guaranteed by design and
characterization testing.
V.
Parameter is a typical value only.
VI.
100% production tested at 25C; guaranteed by design
and characterization testing.
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on
the human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance
degradation or loss of functionality.
Parameter Rating
VD 3.6
V
VDD
3.6 V
DVDD 1.98
V
PVDD 1.98
V
Analog Inputs
V
D
to 0.0 V
Digital Inputs
5 V to 0.0 V
Digital Output Current
20 mA
Operating Temperature
-25C to + 85C
Storage Temperature
-65C to + 150C
Maximum Junction Temperature
150C
Maximum Case Temperature
150C
AD9880
Rev. 0 | Page 7 of 64
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
05087-002
V
DD
RE
D 0
RE
D 1
RE
D 2
RE
D 3
RE
D 4
RE
D 5
RE
D 6
RE
D 7
GND
V
DD
DATACLK
DE
HS
OUT
SOGOUT
VSOU
T
O/E FIELD
SD
A
SC
L
P
W
RDN
V
D
R
AIN0
GND
R
AIN1
V
D
26
I2S1
27
I2S0
28
S/PD
IF
29
GND
30
DV
DD
31
GND
32
DV
DD
33
V
D
34
RX
0
35
RX
0
+
36
GND
37
RX
1
38
RX
1
+
39
GND
2
GREEN 7
3
GREEN 6
4
GREEN 5
7
GREEN 2
6
GREEN 3
5
GREEN 4
1
GND
8
GREEN 1
9
GREEN 0
10
V
DD
12
BLUE 7
13
BLUE 6
14
BLUE 5
15
BLUE 4
16
BLUE 3
17
BLUE 2
18
BLUE 1
19
BLUE 0
20
MCLKIN
21
MCLKOUT
22
SCLK
23
LRCLK
24
I2S3
25
I2S2
11
GND
74
G
AIN0
GND
73
SOGIN0
72
V
D
69
GND
70
SOGIN1
71
G
AIN1
75
68
B
AIN0
67
V
D
66
B
AIN1
64
HSYNC 0
63
HSYNC 1
62
EXTCLK/COAST
61
VSYNC 0
60
VSYNC 1
59
PV
DD
58
GND
57
FILT
56
PV
DD
55
GND
54
PV
DD
53
ALGND
52
MDA
51
MCL
65
GND
40
RX
2
41
RX
2
+
42
GND
43
Rx
C+
44
Rx
C
45
V
D
46
RTE
R
M
47
GND
48
DV
DD
49
DDC_
S
CL
50
DDC_
S
DA
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
PIN 1
AD9880
TOP VIEW
(Not to Scale)
Figure 2. Pin Configuration
Table 4. Complete Pinout List
Pin Type
Pin No.
Mnemonic
Function
Value
INPUTS 79
R
AIN0
Analog Input for Converter R Channel 0
0.0 V to 1.0 V
77
R
AIN1
Analog Input for Converter R Channel 1
0.0 V to 1.0 V
74
G
AIN0
Analog Input for Converter G Channel 0
0.0 V to 1.0 V
71
G
AIN1
Analog Input for Converter G Channel 1
0.0 V to 1.0 V
68
B
B
AIN0
Analog Input for Converter B Channel 0
0.0 V to 1.0 V
66
B
B
AIN1
Analog Input for Converter B Channel 1
0.0 V to 1.0 V
64
HSYNC0
Horizontal SYNC Input for Channel 0
3.3 V CMOS
63
HSYNC1
Horizontal SYNC Input for Channel 1
3.3 V CMOS
61
VSYNC0
Vertical SYNC Input for Channel 0
3.3 V CMOS
60
VSYNC1
Vertical SYNC Input for Channel 1
3.3 V CMOS
73
SOGIN0
Input for Sync-on-Green Channel 0
0.0 V to 1.0 V
70
SOGIN1
Input for Sync-on-Green Channel 1
0.0 V to 1.0 V
62
EXTCLK
External Clock Input--Shares Pin with COAST
3.3 V CMOS
62
COAST
PLL COAST Signal Input--Shares Pin with EXTCLK
3.3 V CMOS
81
PWRDN
Power-Down Control
3.3 V CMOS
AD9880
Rev. 0 | Page 8 of 64
Pin Type
Pin No.
Mnemonic
Function
Value
OUTPUTS
92 to 99
RED [7:0]
Outputs of Red Converter, Bit 7 is MSB
V
DD
2 to 9
GREEN [7:0]
Outputs of Green Converter, Bit 7 is MSB
V
DD
12 to 19
BLUE [7:0]
Outputs of Blue Converter, Bit 7 is MSB
V
DD
89
DATACK
Data Output Clock
V
DD
87
HSOUT
HSYNC Output Clock (Phase-Aligned with DATACK)
V
DD
85
VSOUT
VSYNC Output Clock (Phase-Aligned with DATACK)
V
DD
86
SOGOUT
SOG Slicer Output
V
DD
84
O/E FIELD
Odd/Even Field Output
V
DD
REFERENCES
57
FILT
Connection For External Filter Components For PLL
POWER SUPPLY
80, 76, 72,
67, 45, 33
V
D
Analog Power Supply and DVI Terminators
3.3 V
100, 90, 10
V
DD
Output Power Supply
1.8 V to 3.3 V
59, 56, 54
PV
DD
PLL Power Supply
1.8 V
48, 32, 30
DV
DD
Digital Logic Power Supply
1.8 V
GND
Ground
0
V
CONTROL
83
SDA
Serial Port Data I/O
3.3 V CMOS
82
SCL
Serial Port Data Clock
3.3 V CMOS
HDCP
49
DDC_SCL
HDCP Slave Serial Port Data Clock
3.3 V CMOS
50
DDC_SDA
HDCP Slave Serial Port Data I/O
3.3 V CMOS
51
MCL
HDCP Master Serial Port Data Clock
3.3 V CMOS
52
MDA
HDCP Master Serial Port Data I/O
3.3 V CMOS
AUDIO DATA OUTPUTS
28
S/PDIF
S/PDIF Digital Audio Output
V
DD
27
I2S0
I
2
S Audio (Channels 1, 2)
V
DD
26
I2S1
I
2
S Audio (Channels 3, 4)
V
DD
25
I2S2
I
2
S Audio (Channels 5, 6)
V
DD
24
I2S3
I
2
S Audio (Channels 7, 8)
V
DD
20
MCLKIN
External Reference Audio Clock In
V
DD
21
MCLKOUT
Audio Master Clock Output
V
DD
22
SCLK
Audio Serial Clock Output
V
DD
23
LRCLK
Data Output Clock For Left And Right Audio Channels
V
DD
DIGITAL VIDEO DATA
35
Rx0+
Digital Input Channel 0 True
TMDS
34
Rx0-
Digital Input Channel 0 Complement
TMDS
38
Rx1+
Digital Input Channel 1 True
TMDS
37
Rx1-
Digital Input Channel 1 Complement
TMDS
41
Rx2+
Digital Input Channel 2 True
TMDS
40
Rx2-
Digital Input Channel 2 Complement
TMDS
DIGITAL VIDEO CLOCK INPUTS
43
RxC+
Digital Data Clock True
TMDS
44
RxC-
Digital Data Clock Complement
TMDS
DATA ENABLE
88
DE
Data Enable
3.3 V CMOS
RTERM
46
RTERM
Sets Internal Termination Resistance
500
AD9880
Rev. 0 | Page 9 of 64
Table 5. Pin Function Descriptions
Pin Description
INPUTS
R
AIN0
Analog Input for the Red Channel 0.
G
AIN0
Analog Input for the Green Channel 0.
B
B
AIN0
Analog Input for the Blue Channel 0.
R
AIN1
Analog Input for the Red Channel 1.
G
AIN1
Analog Input for the Green Channel 1.
B
B
AIN1
Analog Input for Blue Channel 1.
High impedance inputs that accept the red, green, and blue channel graphics signals, respectively. The three channels
are identical, and can be used for any colors, but colors are assigned for convenient reference. They accommodate
input signals ranging from 0.5 V to 1.0 V full scale. Signals should be ac-coupled to these pins to support clamp
operation. (see Figure 3 for an input reference circuit).
Rx0+
Digital Input Channel 0 True.
Rx0-
Digital Input Channel 0 Complement.
Rx1+
Digital Input Channel 1 True.
Rx1-
Digital Input Channel 1 Complement.
Rx2+
Digital Input Channel 2 True.
Rx2-
Digital input Channel 2 Complement.
These six pins receive three pairs TMDS (Transition Minimized Differential Signaling) pixel data (at 10X the pixel rate)
from a digital graphics transmitter.
RxC+
Digital Data Clock True.
RxC-
Digital Data Clock Complement.
This clock pair receives a TMDS clock at 1 pixel data rate.
HSYNC0
Horizontal Sync Input Channel 0.
HSYNC1
Horizontal Sync Input Channel 1.
These inputs receive a logic signal that establishes the horizontal timing reference and provides the frequency
reference for pixel clock generation. The logic sense of this pin is controlled by serial register 0x12 Bits 5:4 (Hsync
polarity). Only the leading edge of Hsync is active; the trailing edge is ignored. When Hsync Polarity = 0, the falling
edge of Hsync is used. When Hsync Polarity = 1, the rising edge is active. The input includes a Schmitt trigger for noise
immunity.
VSYNC0
Vertical Sync Input Channel 0.
VSYNC1
Vertical Sync Input Channel 1.
These are the inputs for vertical sync.
SOGIN0
Sync-On-Green Input Channel 0.
SOGIN1
Sync-On-Green Input Channel 1.
These inputs are provided to assist with processing signals with embedded sync, typically on the green channel. The
pin is connected to a high speed comparator with an internally generated threshold. The threshold level can be
programmed in 10 mV steps to any voltage between 10 mV and 330 mV above the negative peak of the input signal.
The default voltage threshold is 150 mV. When connected to an ac-coupled graphics signal with embedded sync, it
produces a noninverting digital output on SOGOUT. (This is usually a composite sync signal, containing both vertical
and horizontal sync (Hsync) information that must be separated before passing the horizontal sync signal to Hsync.)
When not used, this input should be left unconnected. For more details on this function and how it should be
configured, refer to the Hsync and Vsync Inputs section.
EXTCLK/COAST
Coast Input to Clock Generator (Optional).
This input may be used to cause the pixel clock generator to stop synchronizing with Hsync and continue producing a
clock at its current frequency and phase. This is useful when processing signals from sources that fail to produce
horizontal sync pulses during the vertical interval. The Coast signal is generally not required for PC-generated signals.
The logic sense of this pin is controlled by Coast polarity (Register 0x18, Bits 6:5). When not used, this pin may be
grounded and input Coast polarity programmed to 1 (Register 0x18, Pin 5), or tied high (to V
D
through a 10 K resistor)
and input Coast polarity programmed to 0. Input Coast polarity defaults to 1 at power-up. This pin is shared with the
EXTCLK function, which does not affect Coast functionality. For more details on Coast, see the description in the Clock
Generation section.
EXTCLK/COAST External
Clock.
This allows the insertion of an external clock source rather than the internally generated PLL locked clock. This pin is
shared with the Coast function, which will not affect EXTCLK functionality.
AD9880
Rev. 0 | Page 10 of 64
Pin Description
PWRDN
Power-Down Control/Three-State Control.
The function of this pin is programmable via Register 0x26 [2:1].
FILT
External Filter Connection.
For proper operation, the pixel clock generator PLL requires an external filter. Connect the filter shown in Figure 6 to
this pin. For optimal performance, minimize noise and parasitics on this node. For more information see the section on
PCB Layout Recommendations.
OUTPUTS
HSOUT
Horizontal Sync Output.
A reconstructed and phase-aligned version of the Hsync input. Both the polarity and duration of this output can be
programmed via serial bus registers. By maintaining alignment with DATACK and Data, data timing with respect to
horizontal sync can always be determined.
VSOUT
Vertical Sync Output.
The separated Vsync from a composite signal or a direct pass through of the Vsync signal. The polarity of this output
can be controlled via serial bus bit (Register 0x24 [6]).
SOGOUT
Sync-On-Green Slicer Output.
This pin outputs one of four possible signals (controlled by Register 0x1D [1:0]): raw SOG, raw Hsync, regenerated
Hsync from the filter, or the filtered Hsync. See the Sync processing block diagram (see Figure 8) to view how this pin is
connected. (Note: besides slicing off SOG, the output from this pin is not processed on the AD9880. Vsync separation is
performed via the sync separator.
O/E FIELD
Odd/Even Field Bit for Interlaced Video. This output will identify whether the current field (in an interlaced signal) is odd
or even. The polarity of this signal is programmable via Register 0x24[4].
SERIAL PORT
SDA
Serial Port Data I/O for programming AD9880 registers I2C address is 0x98.
SCL
Serial Port Data Clock for programming AD9880 registers.
DDCSDA
Serial Port Data I/O for HDCP communications to transmitter I2C address is 0x74 or 0x76.
DDCSCL
Serial Port Data Clock for HDCP communications to transmitter.
MDA
Serial Port Data I/O to EEPROM with HDCP keys I2C address is 0xA0
MCL
Serial Port Data Clock to EEPROM with HDCP keys.
DATA OUTPUTS
Red [7:0]
Data Output, Red Channel.
Green [7:0]
Data Output, Green Channel.
Blue [7:0]
Data Output, Blue Channel. The main data outputs. Bit 7 is the MSB. The delay from pixel sampling time to output is
fixed, but will be different if the color space converter is used. When the sampling time is changed by adjusting the
phase register, the output timing is shifted as well. The DATACK and HSOUT outputs are also moved, so the timing
relationship among the signals is maintained.
DATA CLOCK
OUTPUT
DATACK
Data Clock Output.
This is the main clock output signal used to strobe the output data and HSOUT into external logic. Four possible output
clocks can be selected with Register 0x25 [7:6]. These are related to the pixel clock (1/2 pixel clock, 1 pixel clock, 2
frequency pixel clock and a 90 phase shifted pixel clock) and they are produced either by the internal PLL clock
generator or EXTCLK and are synchronous with the pixel sampling clock. The polarity of DATACK can also be inverted
via Register 0x24 [0]. The sampling time of the internal pixel clock can be changed by adjusting the phase register.
When this is changed, the pixel-related DATACK timing is shifted as well. The DATA, DATACK, and HSOUT outputs are all
moved, so the timing relationship among the signals is maintained.
AD9880
Rev. 0 | Page 11 of 64
Pin Description
POWER SUPPLY
1
V
D
(3.3 V)
Analog Power Supply.
These pins supply power to the ADCs and terminators. They should be as quiet and filtered as possible.
V
DD
(1.8 V 3.3 V)
Digital Output Power Supply.
A large number of output pins (up to 27) switching at high speed (up to 150 MHz) generates many power supply
transients (noise). These supply pins are identified separately from the V
D
pins so special care can be taken to minimize
output noise transferred into the sensitive analog circuitry. If the AD9880 is interfacing with lower voltage logic, V
DD
may be connected to a lower supply voltage (as low as 1.8 V) for compatibility.
PV
DD
(1.8 V)
Clock Generator Power Supply.
The most sensitive portion of the AD9880 is the clock generation circuitry. These pins provide power to the clock PLL
and help the user design for optimal performance. The designer should provide quiet, noise-free power to these pins.
DV
DD
(1.8 V)
Digital Input Power Supply.
This supplies power to the digital logic.
GND
Ground.
The ground return for all circuitry on chip. It is recommended that the AD9880 be assembled on a single solid ground
plane, with careful attention to ground current paths.
1
The supplies should be sequenced such that VD and VDD are never less than 300 mV below DVDD. At no time should DVDD be more than 300 mV greater than VD or
VDD.
AD9880
Rev. 0 | Page 12 of 64
DESIGN GUIDE
GENERAL DESCRIPTION
The AD9880 is a fully integrated solution for capturing analog
RGB or YUV signals and digitizing them for display on flat
panel monitors, projectors, or PDPs. In addition, the AD9880
has a digital interface for receiving DVI/HDMI signals and
is capable of decoding HDCP encrypted signals through con-
nections to an internal EEPROM. The circuit is ideal for
providing an interface for HDTV monitors or as the front end
to high performance video scan converters.
Implemented in a high-performance CMOS process, the
interface can capture signals with pixel rates of up to 150 MHz.
The AD9880 includes all necessary input buffering, signal dc
restoration (clamping), offset and gain (brightness and contrast)
adjustment, pixel clock generation, sampling phase control, and
output data formatting. Included in the output formatting is a
color space converter (CSC), which accommodates any input
color space and can output any color space. All controls are
programmable via a 2-wire serial interface. Full integration of
these sensitive analog functions makes system design straight-
forward and less sensitive to the physical and electrical
environment.
DIGITAL INPUTS
All digital control inputs (Hsync, Vsync, I2C) on the AD9880
operate to 3.3 V CMOS levels. In addition, all digital inputs
except the TMDS (HDMI/DVI) inputs are 5 V tolerant.
(Applying 5 V to them does not cause any damage.) TMDS
inputs (RX0+/, RX1+/, RX2+/, and RXC+/) must maintain
a 100 differential impedance (through proper PCB layout)
from the connector to the input where they are internally
terminated (50 to 3.3 V). If additional ESD protection is
desired, use of a California Micro Devices (CMD) CM1213
(among others) series low capacitance ESD protection offers 8
kV of protection to the HDMI TMDS lines.
ANALOG INPUT SIGNAL HANDLING
The AD9880 has six high-impedance analog input pins for the
red, green, and blue channels. They accommodate signals
ranging from 0.5 V to 1.0 V p-p.
Signals are typically brought onto the interface board via a
DVI-I connector, a 15-pin D connector, or RCA-type
connectors. The AD9880 should be located as close as practical
to the input connector. Signals should be routed via 75
matched impedance traces to the IC input pins.
At that point the signal should be resistively terminated (75
to the signal ground return) and capacitively coupled to the
AD9880 inputs through 47 nF capacitors. These capacitors form
part of the dc restoration circuit.
In an ideal world of perfectly matched impedances, the best
performance can be obtained with the widest possible signal
bandwidth. The ultrawide bandwidth inputs of the AD9880
(330 MHz) can track the input signal continuously as it moves
from one pixel level to the next, and digitizes the pixel during a
long, flat pixel time. In many systems, however, there are
mismatches, reflections, and noise, which can result in excessive
ringing and distortion of the input waveform. This makes it
more difficult to establish a sampling phase that provides good
image quality. It has been shown that a small inductor in series
with the input is effective in rolling off the input bandwidth
slightly, and providing a high quality signal over a wider range
of conditions. Using a Fair-Rite #2508051217Z0 High Speed
Signal Chip Bead inductor in the circuit shown in Figure 3 gives
good results in most applications.
RGB
INPUT
R
AIN
G
AIN
B
AIN
47nF
75
05087-003
Figure 3. Analog Input Interface Circuit
HSYNC AND VSYNC INPUTS
The interface also takes a horizontal sync signal, which is used
to generate the pixel clock and clamp timing. This can be either
a sync signal directly from the graphics source, or a prepro-
cessed TTL or CMOS level signal.
The Hsync input includes a Schmitt trigger buffer for immunity
to noise and signals with long rise times. In typical PC-based
graphic systems, the sync signals are simply TTL-level drivers
feeding unshielded wires in the monitor cable. As such, no
termination is required.
SERIAL CONTROL PORT
The serial control port is designed for 3.3 V logic. However, it is
tolerant of 5 V logic signals.
OUTPUT SIGNAL HANDLING
The digital outputs are designed to operate from 1.8 V to 3.3 V
(V
DD
).
CLAMPING
RGB Clamping
To properly digitize the incoming signal, the dc offset of the
input must be adjusted to fit the range of the on-board ADC.
Most graphics systems produce RGB signals with black at
ground and white at approximately 0.75 V. However, if sync
signals are embedded in the graphics, the sync tip is often at
ground and black is at 300 mV. Then white is at approximately
1.0 V. Some common RGB line amplifier boxes use emitter-
follower buffers to split signals and increase drive capability.
AD9880
Rev. 0 | Page 13 of 64
This introduces a 700 mV dc offset to the signal, which must be
removed for proper capture by the AD9880.
The key to clamping is to identify a portion (time) of the signal
when the graphic system is known to be producing black. An
offset is then introduced which results in the ADCs producing a
black output (Code 0x00) when the known black input is
present. The offset then remains in place when other signal
levels are processed, and the entire signal is shifted to eliminate
offset errors.
In most pc graphics systems, black is transmitted between active
video lines. With CRT displays, when the electron beam has
completed writing a horizontal line on the screen (at the right
side), the beam is deflected quickly to the left side of the screen
(called horizontal retrace) and a black signal is provided to
prevent the beam from disturbing the image.
In systems with embedded sync, a blacker-than-black signal
(Hsync) is produced briefly to signal the CRT that it is time to
begin a retrace. For obvious reasons, it is important to avoid
clamping on the tip of Hsync. Fortunately, there is virtually
always a period following Hsync called the back porch where a
good black reference is provided. This is the time when
clamping should be done.
Clamp timing employs the AD9880 internal clamp timing
generator. The clamp placement register is programmed with
the number of pixel periods that should pass after the trailing
edge of Hsync before clamping starts. A second register (clamp
duration) sets the duration of the clamp. These are both 8-bit
values, providing considerable flexibility in clamp generation.
The clamp timing is referenced to the trailing edge of Hsync
because, though Hsync duration can vary widely, the back
porch (black reference) always follows Hsync. A good starting
point for establishing clamping is to set the clamp placement to
0x08 (providing 8 pixel periods for the graphics signal to
stabilize after sync) and set the clamp duration to 0x14 (giving
the clamp 20 pixel periods to reestablish the black reference).
For three-level syncs embedded on the green channel, it is
necessary to increase the clamp placement to beyond the posi-
tive portion of the sync. For example, a good clamp placement
(Register 0x19) for a 720p input is 0x26. This delays the start of
clamp by 38 pixel clock cycles after the rising edge of the three-
level sync, allowing plenty of time for the signal to return to a
black reference.
Clamping is accomplished by placing an appropriate charge on
the external input coupling capacitor. The value of this capa-
citor affects the performance of the clamp. If it is too small,
there is a significant amplitude change during a horizontal line
time (between clamping intervals). If the capacitor is too large,
then it takes excessively long for the clamp to recover from a
large change in incoming signal offset. The recommended value
(47 nF) results in recovering from a step error of 100 mV to
within LSB in 10 lines with a clamp duration of 20 pixel
periods on a 75 Hz SXGA signal.
YUV Clamping
YUV graphic signals are slightly different from RGB signals in
that the dc reference level (black level in RGB signals) can be
at the midpoint of the graphics signal rather than the bottom.
For these signals it can be necessary to clamp to the midscale
range of the ADC range (128) rather than bottom of the ADC
range (0).
Clamping to midscale rather than ground can be accomplished
by setting the clamp select bits in the serial bus register. Each of
the three converters has its own selection bit so that they can be
clamped to either midscale or ground independently. These bits
are located in Register 0x1B [7:5]. The midscale reference
voltage is internally generated for each converter.
Auto Offset
The auto-offset circuit works by calculating the required offset
setting to yield a given output code during clamp. When this
block is enabled, the offset setting in the I
2
C is seen as a desired
clamp code rather than an actual offset. The circuit compares
the output code during clamp to the desired code and adjusts
the offset up or down to compensate.
The offset on the AD9880 can be adjusted automatically to a
specified target code. Using this option allows the user to set the
offset to any value and be assured that all channels with the
same value programmed into the target code will match. This
eliminates any need to adjust the offset at the factory. This
function is capable of running continuously anytime the clamp
is asserted.
There is an offset adjust register for each channel, namely the
offset registers at Addresses 0x08, 0x0A, and 0x0C. The offset
adjustment is a signed (twos complement) number with
64 LSB range. The offset adjustment is added to whatever
offset the auto-offset comes up with. For example: using ground
clamp, the target code is set to 4. To get this code, the auto-
offset generates an offset of 68. If the offset adjustment is set to
10, the offset sent to the converter is 78. Likewise, if the offset
adjust is set to 10, the offset sent to the converter is 58. Refer to
application note AN-775, Implementing the Auto-Offset
Function of the AD9880, for a detailed description of how to
use this function.
Sync-on-Green (SOG)
The SOG input operates in two steps. First, it sets a baseline
clamp level off of the incoming video signal with a negative
peak detector. Second, it sets the sync trigger level to a
programmable level (typically 150 mV) above the negative
peak. The SOG input must be ac-coupled to the green analog
input through its own capacitor. The value of the capacitor must
be 1 nF 20%. If SOG is not used, this connection is not
AD9880
Rev. 0 | Page 14 of 64
required. Note that the SOG signal is always negative polarity.
For additional detail on setting the SOG threshold and other
SOG-related functions, see the Sync Processing section.
05087-004
G
AIN
SOG
1nF
R
AIN
47nF
B
AIN
47nF
47nF
Figure 4. Typical Clamp Configuration for RGB/YUV Applications
Clock Generation
A PLL is employed to generate the pixel clock. In this PLL,
the Hsync input provides a reference frequency. A voltage
controlled oscillator (VCO) generates a much higher pixel clock
frequency. This pixel clock is divided by the PLL divide value
(Registers 0x01 and 0x02) and phase compared with the Hsync
input. Any error is used to shift the VCO frequency and
maintain lock between the two signals.
The stability of this clock is a very important element in provi-
ding the clearest and most stable image. During each pixel time,
there is a period during which the signal slews from the old
pixel amplitude and settles at its new value. This is followed by a
time when the input voltage is stable before the signal must slew
to a new value. The ratio of the slewing time to the stable time is
a function of the bandwidth of the graphics DAC and the
bandwidth of the transmission system (cable and termination).
It is also a function of the overall pixel rate. Clearly, if the
dynamic characteristics of the system remain fixed, then the
slewing and settling time is likewise fixed. This time must be
subtracted from the total pixel period, leaving the stable period.
At higher pixel frequencies, the total cycle time is shorter and
the stable pixel time also becomes shorter.
PIXEL CLOCK
INVALID SAMPLE TIMES
05087-005
Figure 5. Pixel Sampling Times
Any jitter in the clock reduces the precision with which the
sampling time can be determined and must also be subtracted
from the stable pixel time. Considerable care has been taken in
the design of the AD9880's clock generation circuit to minimize
jitter. The clock jitter of the AD9880 is less than 13% of the total
pixel time in all operating modes, making the reduction in the
valid sampling time due to jitter negligible.
The PLL characteristics are determined by the loop filter design,
the PLL charge pump current, and the VCO range setting. The
loop filter design is illustrated in Figure 6. Recommended set-
tings of the VCO range and charge pump current for VESA
standard display modes are listed in Table 8.
C
P
8nF
C
Z
80nF
R
Z
1.5k
FILT
PV
D
05087-006
Figure 6. PLL Loop Filter Detail
Four programmable registers are provided to optimize the
performance of the PLL. These registers are
The 12-Bit Divisor Register. The input Hsync frequency
range can be any frequency which, combined with the
PLL_Div, does not exceed the VCO range . The PLL multi-
plies the frequency of the Hsync signal, producing pixel
clock frequencies in the range of 10 MHz to 100 MHz. The
divisor register controls the exact multiplication factor.
The 2-Bit VCO Range Register. To improve the noise
performance of the AD9880, the VCO operating frequency
range is divided into four overlapping regions. The VCO
range register sets this operating range. The frequency
ranges for the lowest and highest regions are shown in
Table 6.
Table 6.
VCORNGE Pixel
Rate
Range
00 12-30
01 30-60
10 60-120
11 120-150
The 5-Bit Phase Adjust Register. The phase of the
generated sampling clock can be shifted to locate an
optimum sampling point within a clock cycle. The phase
adjust register provides 32 phase-shift steps of 11.25 each.
The Hsync signal with an identical phase shift is available
through the HSOUT pin.
The COAST pin or the internal Coast is used to allow the PLL
to continue to run at the same frequency, in the absence of the
incoming Hsync signal or during disturbances in Hsync (such
as equalization pulses). This can be used during the vertical
sync period or any other time that the Hsync signal is unavail-
able. The polarity of the Coast signal can be set through the
Coast polarity register. Also, the polarity of the Hsync signal
can be set through the Hsync polarity register. For both Hsync
and Coast, a value of 1 is active high. The internal Coast
function is driven off the Vsync signal, which is typically a time
when Hsync signals can be disrupted with extra equalization
pulses.
AD9880
Rev. 0 | Page 15 of 64
Power Management
The AD9880 uses the activity detect circuits, the active interface
bits in the serial bus, the active interface override bits, the
power-down bit, and the power-down pin to determine the
correct power state. There are four power states: full-power,
seek mode, auto power-down and power-down.
Table 7 summarizes how the AD9880 determines which power
mode to be in and which circuitry is powered on/off in each of
these modes. The power-down command has priority and then
the automatic circuitry. The power-down pin (Pin 81--polarity
set by Register 0x26[3]) can drive the chip into four power-
down options. Bits 2 and 1 of Register 0x26 control these four
options. Bit 0 controls whether the chip is powered down or the
outputs are placed in high impedance mode (with the exception
of SOG). Bits 7 to 4 of Register 0x26 control whether the
outputs, SOG, Sony Philips digital interface (SPDIF ) or I2S (IIS
or Inter IC sound bus) outputs are in high impedance mode or
not. See the 2-Wire Serial Control Register Detail section for
the details.
Table 7. Power-Down Mode Descriptions
Inputs
Mode Power-Down
1
Sync Detect
2
Auto PD Enable
3
Power-On or Comments
Full Power
1
1
X
Everything
Seek Mode
1
0
0
Everything
Seek Mode
1
0
1
Serial bus, sync activity detect, SOG, band gap
reference
Power-Down 0
X
Serial bus, sync activity detect, SOG, band gap
reference
1
Power-down is controlled via Bit 0 in Serial Bus Register 0x26.
2
Sync detect is determined by OR'ing Bits 7 to 2 in Serial Bus Register 0x15.
3
Auto power-down is controlled via Bit 7 in Serial Bus Register 0x27
Table 8. Recommended VCO Range and Charge Pump Current Settings for Standard Display Formats
Standard
Resolution
Refresh Rate
Horizontal Frequency
Pixel Rate
VCO Range
1
Current
VGA
640 480
60 Hz
31.5 kHz
25.175 MHz
00
101
72 Hz
37.7 kHz
31.500 MHz
01
011
75 Hz
37.5 kHz
31.500 MHz
01
100
85 Hz
43.3 kHz
36.000 MHz
01
100
SVGA
800 600
56 Hz
35.1 kHz
36.000 MHz
01
100
60 Hz
37.9 kHz
40.000 MHz
01
101
72 Hz
48.1 kHz
50.000 MHz
01
110
75 Hz
46.9 kHz
49.500 MHz
01
110
85 Hz
53.7 kHz
56.250 MHz
01
110
XGA
1024 768
60 Hz
48.4 kHz
65.000 MHz
10
011
70 Hz
56.5 kHz
75.000 MHz
10
100
75 Hz
60.0 kHz
78.750 MHz
10
100
80 Hz
64.0 kHz
85.500 MHz
10
101
85 Hz
68.3 kHz
94.500 MHz
10
110
SXGA
1280 1024
60 Hz
64.0 kHz
108.000 MHz
10
110
1280 1024
75 Hz
80.0 kHz
135.000 MHz
11
110
TV
480i
60 Hz
15.75 kHz
13.51 MHz
00
010
480p
60 Hz
31.47 kHz
27 MHz
00
101
720p
60 Hz
45 kHz
74.25 MHz
10
100
1035i
60 Hz
33.75 kHz
74.25 MHz
10
100
1080i
60 Hz
33.75 kHz
74.25 MHz
10
100
1080p
60 Hz
67.5 KHz
148.5 MHz
11
110
1
These are preliminary recommendations for the analog PLL and are subject to change without notice.
AD9880
Rev. 0 | Page 16 of 64
TIMING
The output data clock signal is created so that its rising edge
always occurs between data transitions and can be used to latch
the output data externally.
There is a pipeline in the AD9880, which must be flushed
before valid data becomes available. This means 23 data sets are
presented before valid data is available.
The timing diagram in Figure 7 shows the operation of the
AD9880.
t
PER
t
DCYCLE
t
SKEW
DATACK
DATA
HSOUT
05087-007
Figure 7. Output Timing
Hsync Timing
Horizontal Sync (Hsync) is processed in the AD9880 to
eliminate ambiguity in the timing of the leading edge with
respect to the phase-delayed pixel clock and data.
The Hsync input is used as a reference to generate the pixel
sampling clock. The sampling phase can be adjusted, with
respect to Hsync, through a full 360 in 32 steps via the phase
adjust register (to optimize the pixel sampling time). Display
systems use Hsync to align memory and display write cycles, so
it is important to have a stable timing relationship between the
Hsync output (HSOUT) and data clock (DATACK).
Three things happen to Hsync in the AD9880. First, the polarity
of Hsync input is determined and thus has a known output
polarity. The known output polarity can be programmed either
active high or active low (Register 0x24, Bit 7). Second, HSOUT
is aligned with DATACK and data outputs. Third, the duration
of HSOUT (in pixel clocks) is set via Register 0x23. HSOUT is
the sync signal that should be used to drive the rest of the
display system.
Coast Timing
In most computer systems, the Hsync signal is provided
continuously on a dedicated wire. In these systems, the Coast
input and function are unnecessary, and should not be used and
the pin should be permanently connected to the inactive state.
In some systems, however, Hsync is disturbed during the verti-
cal sync period (Vsync). In some cases, Hsync pulses disappear.
In other systems, such as those that employ composite sync
(Csync) signals or embedded SOG, Hsync includes equalization
pulses or other distortions during Vsync. To avoid upsetting the
clock generator during Vsync, it is important to ignore these
distortions. If the pixel clock PLL sees extraneous pulses, it
attempts to lock to this new frequency, and changes frequency
by the end of the Vsync period. It then takes a few lines of
correct Hsync timing to recover at the beginning of a new
frame, resulting in a tearing of the image at the top of the
display.
The Coast input is provided to eliminate this problem. It is an
asynchronous input that disables the PLL input and allows the
clock to free run at its then-current frequency. The PLL can free
run for several lines without significant frequency drift.
Coast can be generated internally by the AD9880 (see
Register 0x12 [1]), can be driven directly from a Vsync input,
or can be provided externally by the graphics controller.
Sync Processing
The inputs of the sync processing section of the AD9880 are
combinations of digital Hsyncs and Vsyncs, analog sync-on-
green, or sync-on-Y signals, and an optional external Coast
signal. From these signals it generates a precise, jitter-free (9%
or less at 95 MHz) clock from its PLL; an odd-/even-field signal;
Hsync and Vsync out signals; a count of Hsyncs per Vsync; and
a programmable SOG output. The main sync processing blocks
are the sync slicer, sync separator, Hsync filter, Hsync regen-
erator, Vsync filter, and Coast generator.
The sync slicer extracts the sync signal from the green graphics
or luminance video signal that is connected to the SOGIN input
and outputs a digital composite sync. The sync separator's task
is to extract Vsync from the composite sync signal, which can
come from either the sync slicer or the Hsync input. The Hsync
filter is used to eliminate any extraneous pulses from the Hsync
or SOGIN inputs, outputting a clean, low-jitter signal that is
appropriate for mode detection and clock generation. The
Hsync regenerator is used to recreate a clean, although not low
jitter, Hsync signal that can be used for mode detection and
counting Hsyncs per Vsync. The Vsync filter is used to elimi-
nate spurious Vsyncs, maintain a stable timing relationship
between the Vsync and Hsync output signals, and generate the
odd/even field output. The Coast generator creates a robust
Coast signal that allows the PLL to maintain its frequency in
the absence of Hsync pulses.
AD9880
Rev. 0 | Page 17 of 64
Sync Slicer
The purpose of the sync slicer is to extract the sync signal from
the green graphics or luminance video signal that is connected
to the SOGIN input. The sync signal is extracted in a two step
process. First, the SOG input (typically 0.3 V below the black
level) is detected and clamped to a known dc voltage. Next, the
signal is routed to a comparator with a variable trigger level (set
by Register 0x1D, Bits [7:3]), but nominally 0.128 V above the
clamped voltage. The sync slicer output is a digital composite
sync signal containing both Hsync and Vsync information (see
Figure 9).
AD9880
PLL CLOCK
GENERATOR
HSYNC FILTER
AND
REGENERATOR
HSYNC 0
SOG OUT
HSYNC
COAST
DATACK
SOGIN 0
COAST
CHANNEL
SELECT
VSYNC 1
ODD/EVEN
FIELD
MUX
MUX
MUX
RH3
FH4
SP
5
MUX
1
ACTIVITY DETECT
2
POLARITY DETECT
3
REGENERATED HSYNC
4
FILTERED HSYNC
5
SET POLARITY
SP
5
AD
1
PD
2
PD
2
AD
1
PD2
AD
1
PD2
SYNC
SLICER
SYNC
SLICER
VSYNC 0
HSYNC 1
HSYNC OUT
VSYNC OUT
SOGIN 1
HSYNC/VSYNC
COUNTER
REG 26H, 27H
SYNC
PROCESSOR
AND
VSYNC FILTER
MUX
MUX
PLL SYNC FILTER EN
0x21:6
SP SYNC FILTER EN
0x21:7
SOGOUT SELECT
0x24:2,1
[0x11:7]
HSYNC
SELECT
[0x11:3]
COAST SELECT
0x12:1
VSYNC FILTER EN
0x21:5
FILTER COAST VSYNC
0x12:0
VSYNC
VSYNC
FILTERED
VSYNC
05087-008
AD
1
AD
1
AD
1
SP
5
SP
5
MUX
MUX
MUX
Figure 8. Sync Processing Block Diagram
04740-015
SOG INPUT
SOGOUT OUTPUT
CONNECTED TO
HSYNCIN
NEGATIVE PULSE WIDTH = 40 SAMPLE CLOCKS
COMPOSITE
SYNC
AT HSYNCIN
VSYNCOUT
FROM SYNC
SEPARATOR
300mV
300mV
700mV MAXIMUM
0mV
Figure 9. Sync Slicer and Sync Separator Output
AD9880
Rev. 0 | Page 18 of 64
Sync Separator
As part of sync processing, the sync separator's task is to extract
Vsync from the composite sync signal. It works on the idea that
the Vsync signal stays active for a much longer time than the
Hsync signal. By using a digital low-pass filter and a digital
comparator, it rejects pulses with small durations (such as
Hsyncs and equalization pulses) and only passes pulses with
large durations, such as Vsync (see Figure 9).
The threshold of the digital comparator is programmable for
maximum flexibility. To program the threshold duration, write
a value (N) to Register 0x11. The resulting pulse width is
N 200 ns. So, if N = 5 the digital comparator threshold is 1 s.
Any pulses less than 1 s is rejected, while any pulse greater
than 1 s passes through.
The sync separator on the AD9880 is simply an 8-bit digital
counter with a 6 MHz clock. It works independently of the
polarity of the composite sync signal. Polarities are determined
elsewhere on the chip. The basic idea is that the counter counts
up when Hsync pulses are present. But since Hsync pulses are
relatively short in width, the counter only reaches a value of N
before the pulse ends. It then starts counting down until
eventually reaching 0 before the next Hsync pulse arrives. The
specific value of N varies for different video modes, but is
always less than 255. For example with a 1 s width Hsync, the
counter only reaches 5 (1 s/200 ns = 5). Now, when Vsync is
present on the composite sync the counter also counts up.
However, since the Vsync signal is much longer, it counts to a
higher number, M. For most video modes, M is at least 255.
So, Vsync can be detected on the composite sync signal by
detecting when the counter counts to higher than N. The
specific count that triggers detection, T, can be programmed
through the Serial Register 0x11.
Once Vsync has been detected, there is a similar process to
detect when it goes inactive. At detection, the counter first
resets to 0, then starts counting up when Vsync finishes.
Similarly to the previous case, it detects the absence of Vsync
when the counter reaches the threshold count, T. In this way, it
rejects noise and/or serration pulses. Once Vsync is detected to
be absent, the counter resets to 0 and begins the cycle again.
There are two things to keep in mind when using the sync
separator. First, the resulting clean Vsync output is delayed
from the original Vsync by a duration equal to the digital
comparator threshold (N 200 ns). Second, there is some
variability to the 200 ns multiplier value. The maximum varia-
bility over all operating conditions is 20% (160 ns to 240 ns).
Since normal Vsync and Hsync pulse widths differ by a factor of
about 500 or more, 20% variability is not an issue.
Hsync Filter and Regenerator
The Hsync filter is used to eliminate any extraneous pulses from
the Hsync or SOGIN inputs, outputting a clean, low-jitter signal
that is appropriate for mode detection and clock generation.
The Hsync regenerator is used to recreate a clean, although not
low jitter, Hsync signal that can be used for mode detection and
counting Hsyncs per Vsync. The Hsync regenerator has a high
degree of tolerance to extraneous and missing pulses on the
Hsync input, but is not appropriate for use by the PLL in
creating the pixel clock because of jitter.
The Hsync regenerator runs automatically and requires no
setup to operate. The Hsync filter requires the setting up of a
filter window. The filter window sets a periodic window of time
around the regenerated Hsync leading edge where valid Hsyncs
are allowed to occur. The general idea is that extraneous pulses
on the sync input occur outside of this filter window and thus
are filtered out. To set the filter window timing, program a value
(x) into Register 0x20. The resulting filter window time is x
times 25 ns around the regenerated Hsync leading edge. Just
as for the sync separator threshold multiplier, allow a 20%
variance in the 25 ns multiplier to account for all operating
conditions (20 ns to 30 ns range).
A second output from the Hsync filter is a status bit (Reg-
ister 0x16[0]) that tells whether extraneous pulses are present
on the incoming sync signal or not. Extraneous pulses are often
included for copy protection purposes; this status bit can be
used to detect that.
The filtered Hsync (rather than the raw Hsync/SOGIN signal)
for pixel clock generation by the PLL is controlled by
Register 0x21[6]. The regenerated Hsync (rather than the
raw Hsync/SOGIN signal) for sync processing is controlled by
Register 0x21[7]. Use of the filtered Hsync and regenerated
Hsync is recommended. See Figure 10 for an illustration of a
filtered Hsync.
AD9880
Rev. 0 | Page 19 of 64
HSYNCOUT
VSYNC
FILTER
WINDOW
EXPECTED
EDGE
FILTER
WINDOW
EQUALIZATION
PULSES
HSYNCIN
05087-010
Figure 10. Sync Processing Filter
Vsync Filter and Odd/Even Fields
The Vsync filter is used to eliminate spurious Vsyncs, maintain
a consistent timing relationship between the Vsync and Hsync
output signals, and generate the odd/even field output.
The filter works by examining the placement of Vsync with
respect to Hsync and, if necessary, slightly shifting it in time at
the VSOUT output. The goal is to keep the Vsync and Hsync
leading edges from switching at the same time, eliminating
confusion as to when the first line of a frame occurs. Enabling
the Vsync filter is done with Register 0x21[5]. Use of the Vsync
filter is recommended for all cases, including interlaced video,
and is required when using the Hsync per Vsync counter.
Figure 12 illustrates even/odd field determination in two
situations.
FIELD 1
FIELD 0
SYNC SEPARATOR THRESHOLD
FIELD 1
FIELD 0
2
3
2
1
4
4
3
1
HSYNCIN
VSYNCIN
VSYNCOUT
O/E FIELD
EVEN FIELD
QUADRANT
05087-011
Figure 11.
FIELD 1
FIELD 0
SYNC SEPARATOR THRESHOLD
FIELD 1
FIELD 0
2
3
2
1
4
4
3
1
HSYNCIN
VSYNCIN
VSYNCOUT
O/E FIELD
ODD FIELD
QUADRANT
05087-012
Figure 12. Vsync Filter--Odd/Even
AD9880
Rev. 0 | Page 20 of 64
HDMI RECEIVER
The HDMI receiver section of the AD9880 allows the reception
of a digital video stream, which is backward-compatible with
DVI and able to accommodate not only video of various for-
mats (RGB, YCrCb 4:4:4, 4:2:2), but also up to eight channels of
audio. Infoframes are transmitted carrying information about
the video format, audio clocks, and many other items necessary
for a monitor to utilize fully the information stream available.
The earlier digital visual interface (DVI) format was restricted
to an RGB 24 bit color space only. Embedded in this data
stream were Hsyncs, Vsyncs and display enable (DE) signals,
but no audio information. The HDMI specification allows
trans-mission of all the DVI capabilities, but adds several
YCrCb formats that make the inclusion of a programmable
color space converter (CSC) a very desirable feature. With this,
the scaler following the AD9880 can specify that it always
wishes to receive a particular format, for instance, 4:2:2 YCrCb
regardless of the transmitted mode. If RGB is sent, the CSC can
easily convert that to 4:2:2 YCrCb while relieving the scaler of
this task.
In addition, the HDMI specification supports the transmission
of up to eight channels of S/PDIF or I2S audio. The audio
information is packetized and transmitted during the video
blanking periods along with specific information about the
clock frequency. Part of this audio information (Audio
Infoframe) tells the user how many channels of audio, where
they should be placed, information regarding the source (make,
model), and other data.
DE GENERATOR
The AD9880 has an onboard generator for DE, for start of
active video (SAV), and for end of active video (EAV), all of
which are necessary for describing the complete data stream for
a BT656 compatible output. In addition to this particular
output, it is possible to generate the DE for cases in which a
scaler is not planned to be used. This signal alerts the following
circuitry as to which are displayable video pixels.
4:4:4 TO 4:2:2 FILTER
The AD9880 contains a filter which allows it to convert a signal
from YCrCb 4:4:4 to YCrCb 4:2:2 while maintaining the
maximum accuracy and fidelity of the original signal.
Input Color space to Output Color space
The AD9880 can accept a wide variety of input formats and
either retain that format or convert to another. Input formats
supported are
4:4:4 YCrCb 8 bit
4:2:2 YCrCb 8, 10, and 12 bit
RGB 8-bit
Output modes supported are
4:4:4 YCrCb 8 bits
4:2:2 YCrCb 8, 10, and 12 bits
Dual 4:2:2 YCrCb 8 bits.
Color space Conversion (CSC) Matrix
The color space conversion (CSC) matrix in the AD9880
consists of three identical processing channels. In each channel,
three input values are multiplied by three separate coefficients.
Also included are an offset value for each row of the matrix and
a scaling multiple for all values. Each value has a 13 bit twos
complement resolution to ensure the signal integrity is main-
tained. The CSC is designed to run at speeds up to 150 MHz
supporting resolutions up to 1080 p at 60 Hz. With any-to-any
color space support, formats such as RGB, YUV, YCbCr, and
others are supported by the CSC.
The main inputs, Rin, Gin, and Bin come from the 8- to 12-bit
inputs from each channel. These inputs are based on the input
format detailed in Table 7 to Table 15. The mapping of these
inputs to the CSC inputs is shown in Table 9.
Table 9. CSC Port Mapping
Input Channel
CSC Input Channel
R/CR R
IN
Gr/Y G
IN
B/CB B
B
IN
One of the three channels is represented in Figure 13. In each
processing channel the three inputs are multiplied by three
separate coefficients marked a1, a2, and a3. These coefficients
are divided by 4096 to obtain nominal values ranging from
0.9998 to +0.9998. The variable labeled a4 is used as an offset
control. The CSC_mode setting is the same for all three
processing channels. This multiplies all coefficients and offsets
by a factor of 2
csc_mode
.
The functional diagram for a single channel of the CSC as
shown in Figure 13 is repeated for the remaining G and B
channels. The coefficients for these channels are b1, b2, b3, b4,
c1, c2, c3, and c4.
05087-
013
2
2
1
0
a1[12:0]
a2[12:0]
a3[12:0]
R
IN
[11:0]
B
IN
[11:0]
G
IN
[11:0]
+
4
CSC_MODE[1:0]
a4[12:0]
R
OUT
[11:0]
+
1
4096
1
4096
1
4096
+
Figure 13. Single CSC Channel
AD9880
Rev. 0 | Page 21 of 64
A programming example and register settings for several
common conversions are listed in the Color Space Converter
(CSC) Common Settings.
For a detailed functional description and more programming
examples, please refer to the application note AN-795, AD9880
Color space Converter User's Guide.
AUDIO PLL SETUP
Data contained in the Audio Infoframes among other registers
define for the AD9880 HDMI receiver not only the type of
audio, but the sample frequency. It also contains information
about the N and CTS values used to recreate the clock. With
this information it is possible to regenerate the audio sampling
frequency. The audio clock is regenerated by dividing the 20-bit
CTS value into the TMDS clock, then multiplying by the 20-bit
N value. This yields a multiple of the fs (sampling frequency) of
either 128 fs or 256 fs. It is possible for this to be specified
up to 1024 fs.
05087-014
SINK DEVICE
SOURCE DEVICE
1
N AND CTS VALUES ARE TRANSMITTED USING THE
"AUDIO CLOCK REGENERATION" PACKET. VIDEO
CLOCK IS TRANSMITTED ON TMDS CLOCK CHANNEL.
128
f
S
N
VIDEO
CLOCK
128
f
S
TMDS
CLOCK
N
1
CTS
1
DIVIDE
BY
N
CYCLE
TIME
COUNTER
REGISTER
N
DIVIDE
BY
CTS
MUTIPLY
BY
N
Figure 14. N and CTS for Audio Clock
AUDIO BOARD LEVEL MUTING
The audio can be muted through the Infoframes or locally via
the serial bus registers. This can be controlled with
Register R0x57, Bits [7:4].
AVI Infoframes
Contained within the HDMI TMDS transmission are
Infoframes containing specific information for the monitor
such as
Audio information
o
2 to 8 channels of audio identified
o
Audio coding
o
Audio sampling frequency
Speaker placement
N and CTS values (for reconstruction of the audio)
Muting
Source information
o
CD
o
SACD
o
DVD
Video information
o
Video ID Code (per CEA861B)
o
Color space
o
Aspect ratio
o
Horizontal and vertical bar information
o
MPEG frame information (I, B, or P frame)
Vendor (transmitter source) information
o
Vendor name and product model
This information is the fundamental difference between DVI
and HDMI transmissions and is located in read-only registers
R0x5A to R0xEE. In addition to this information, registers are
provided that indicate that new information has been received.
Registers with addresses ending in 0xX7 or 0xXF beginning at
R0x87 contain the new data flags (NDF) information. All of
these registers contain the same information and all are reset
once any of them are read. Although there is no external
interrupt signal, it is very straightforward for the user to read
any of these registers and see if there is new information to be
processed.
TIMING DIAGRAMS
The following timing diagrams show the operation of the
AD9880.The output data clock signal is created so that its rising
edge always occurs between data transitions and can be used to
latch the output data externally. There is a pipeline in the
AD9880, which must be flushed before valid data becomes
available. This means six data sets are presented before valid
data is available.
AD9880
Rev. 0 | Page 22 of 64
DATAIN
P0
P1
P2
P5
P3
P4
P9
P6
P8
P10
P11
P7
HSIN
DATACLK
8 CLOCK CYCLE DELAY
DATAOUT
P0
P1
P2
P3
2 CLOCK CYCLE DELAY
HSOUT
05087-015
Figure 15. RGB ADC Timing
DATAIN
P0
P1
P2
P5
P3
P4
P9
P6
P8
P10
P11
P7
HSIN
DATACLK
8 CLOCK CYCLE DELAY
CB/CROUT
B0
R0
B2
R2
YOUT
Y0
Y1
Y2
Y3
2 CLOCK CYCLE DELAY
1. PIXEL AFTER HSOUT CORRESPONDS TO BLUE INPUT.
2. EVEN NUMBER OF PIXEL DELAY BETWEEN HSOUT AND DATAOUT.
HSOUT
05087-016
Figure 16. YCrCb ADC Timing
Table 10.
Port Red
Green
Blue
Bit
7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0
4:4:4
Red/Cr [7:0]
Green/Y [7:0]
Blue/Cb [7:0]
4:2:2
CbCr [7:0]
Y [7:0]
DDR 4:2:2
CbCr
Y,Y
DDR
1
G [3:0]
DDR
B [7:4]
DDR
B [3:0]
DDR 4:2:2
CbCr [11:0]
4:4:4 DDR
DDR
R [7:0]
DDR
G [7:4]
DDR 4:2:2
Y,Y [11:0]
4:2:2-12
CbCr [11:0]
Y [11:0]
1
Arrows in the table indicate clock edge. Rising edge of clock =
, falling edge = .
AD9880
Rev. 0 | Page 23 of 64
2-WIRE SERIAL REGISTER MAP
The AD9880 is initialized and controlled by a set of registers that determines the operating modes. An external controller is employed to
write and read the control registers through the 2-wire serial interface port.
Table 11. Control Register Map
Hex
Address
Read/Write
or Read Only
Bits
Default
Value
Register Name
Description
0x00
Read
[7:0]
00000000
Chip Revision
Chip revision ID. Revision is read [7:4]. [3:0].
0x01
Read/Write
[7:0]
01101001
PLL Divider MSB
PLL feedback divider value MSB.
0x02
Read/Write
[7:4]
1101****
PLL Divider
PLL feedback divider value.
0x03
Read/Write
[7:6]
01******
VCO Range
VCO range.
[5:3]
**001***
Charge Pump
Charge pump current control for PLL.
[2]
*****0**
External Clock Enable
Selects the external clock input rather that the internal PLL
clock.
0x04 Read/Write
[7:3]
10000***
Phase
Adjust
Selects the clock phase to use for the ADC clock.
0x05 Read/Write
[7:0]
10000000
Red
Gain
Controls the gain of the red channel PGA. 0 = low gain,
255 = high gain.
0x06 Read/Write
[7:0]
10000000
Green
Gain
Controls the gain of the green channel PGA. 0 = low gain,
255 = high gain.
0x07 Read/Write
[7:0]
10000000
Blue
Gain
Controls the gain of the blue channel PGA. 0 = low gain,
255 = high gain.
0x08
Read/Write
[7:0]
00000000
Red Offset Adjust
User adjustment of auto offset. Allows user control of brightness.
0x09
Read/Write
[7:0]
10000000
Red Offset
Red offset/target code. 0 = small offset, 255 = large offset.
0x0A
Read/Write
[7:0]
00000000
Green Offset Adjust
User adjustment of auto offset. Allows user control of brightness.
0x0B Read/Write
[7:0]
10000000
Green
Offset
Green
offset/target code. 0 = small offset, 255 = large offset.
0x0C
Read/Write
[7:0]
00000000
Blue Offset Adjust
User adjustment of auto offset. Allows user control of brightness.
0x0D
Read/Write
[7:0]
10000000
Blue Offset
Blue offset/target code. 0 = small offset, 255 = large offset.
0x0E Read/Write
[7:0]
00100000
Sync Separator
Threshold
Selects the maximum Hsync pulse width for composite sync
separation.
0x0F Read/Write
[7:2]
010000**
SOG Comparator
Threshold Enter
The enter level for the SOG slicer. Must be less than or equal to
the exit level.
0x10 Read/Write
[7:2]
010000**
SOG Comparator
Threshold Exit
The exit level for the SOG slicer. Must be greater than or equal to
the enter level.
0x11
Read/Write
[7]
0*******
Hsync Source
0 = Hsync.
1 = SOG.
[6]
*0******
Hsync Source
Override
0 = auto Hsync source.
1 = manual Hsync source.
[5]
**0*****
Vsync Source
0 = Vsync.
1 = Vsync from SOG.
[4]
***0****
Vsync Source
Override
0 = auto Hsync source.
1 = manual Hsync source.
[3]
****0***
Channel Select
0 = Channel 0.
1 = Channel 1.
[2]
*****0**
Channel Select
Override
0 = autochannel select.
1 = manual channel select.
[1]
******0*
Interface Select
0 = analog interface.
1 = digital interface.
[0]
*******0
Interface Override
0 = auto-interface select.
1 = manual interface select.
AD9880
Rev. 0 | Page 24 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0x12
Read/Write
[7]
1*******
Input Hsync Polarity
0 = active low.
1 = active high.
[6]
*0******
Hsync Polarity
Override
0 = auto Hsync polarity.
1 = manual Hsync polarity.
[5]
**1*****
Input Vsync Polarity
0 = active low.
1 = active high.
[4]
***0****
Vsync Polarity
Override
0 = auto Vsync polarity.
1 = manual Vsync polarity.
[3]
****1***
Input Coast Polarity
0 = active low.
1 = active high.
[2]
*****0**
Coast Polarity
Override
0 = auto Coast polarity.
1 = manual Coast polarity.
[1]
******0*
Coast Source
0 = internal Coast.
1 = external Coast.
[0]
*******1
Filter Coast Vsync
0 = Use raw Vsync for Coast generation.
1 = Use filtered Vsync for Coast generation.
0x13
Read/Write
[7:0]
00000000
Precoast
Number of Hsync periods before Vsync to Coast.
0x14 Read/Write
[7:0]
00000000
Postcoast
Number
of Hsync periods after Vsync to Coast.
0x15
Read
[7]
0*******
Hsync 0 Detected
0 = not detected.
1 = detected.
[6]
*0******
Hsync 1 Detected
0 = not detected.
1 = detected.
[5]
**0*****
Vsync 0 Detected
0 = not detected.
1 = detected.
[4]
***0****
Vsync 1 Detected
0 = not detected.
1 = detected.
[3]
****0***
SOG 0 Detected
0 = not detected.
1 = detected.
[2]
*****0**
SOG1 Detected
0 = not detected.
1 = detected.
[1]
******0*
Coast Detected
0 = not detected.
1 = detected.
0x16
Read
[7]
0*******
Hsync 0 Polarity
0 = active low.
1 = active high.
[6]
*0******
Hsync 1 Polarity
0 = active low.
1 = active high.
[5]
**0*****
Vsync 0 Polarity
0 = active low.
1 = active high.
[4]
***0****
Vsync 1 Polarity
0 = active low.
1 = active high.
[3]
****0***
Coast Polarity
0 = active low.
1 = active high.
[2]
*****0**
Pseudo Sync
Detected
0 = not detected.
1 = detected.
[1]
******0*
Sync Filter Locked
0 = not locked.
1 = locked.
[0]
*******0
Bad Sync Detect
0 = not detected.
1 = detected.
AD9880
Rev. 0 | Page 25 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0x17 Read
[3:0]
****0000
Hsyncs Per Vsync
MSB
MSB of Hsyncs per Vsync.
0x18 Read
[7:0]
00000000
Hsyncs
Per
Vsync
Hsyncs per Vsync count.
0x19 Read/Write
[7:0]
00001000
Clamp
Placement Number of pixel clocks after trailing edge of Hsync to begin
clamp.
0x1A
Read/Write
[7:0]
00010100
Clamp Duration
Number of pixel clocks to clamp.
0x1B
Read/Write
[7]
0*******
Red Clamp Select
0 = clamp to ground.
1 = clamp to midscale.
[6]
*0******
Green Clamp Select
0 = clamp to ground.
1 = clamp to midscale.
[5]
**0*****
Blue Clamp Select
0 = clamp to ground.
1 = clamp to midscale.
[4]
***0****
Clamp During Coast
Enable
0 = don't clamp during Coast.
1 = clamp during Coast.
[3]
****0***
Clamp Disable
0 = internal clamp enabled.
1 = internal clamp disabled.
[1]
******1*
Programmable
Bandwidth
0 = low bandwidth.
1 = full bandwidth.
[0]
*******0
Hold Auto Offset
0 = normal auto offset operation.
1 = hold current offset value.
0x1C
Read/Write
[7]
0*******
Auto Offset Enable
0 = manual offset.
1 = auto offset using offset as target code.
[6:5]
*10*****
Auto Offset
00 = every clamp.
Update Mode
01 = every 16 clamps.
10 = every 64 clamps.
11 = Every Vsync.
[4:3]
***01***
Difference Shift
00 = 100% of difference used to calculate new offset.
Amount
01 = 50%.
10 = 25%.
11 = 12.5%.
[2]
*****1**
Auto Jump Enable
0 = normal operation.
1 = if code > 15 codes off then offset is jumped to the predicted
offset necessary to fix the > 15 code mismatch.
[1]
******1*
Post Filter Enable
0 = disable post filer.
1 = enable post filter.
Post filter reduces update rate by 1/6 and requires that all six
updates recommend a change before changing the offset. This
prevents unwanted offset changes.
[0]
*******0
Toggle Filter Enable
The toggle filter looks for the offset to toggle back and forth and
holds it if triggered. This is to prevent toggling in case of missing
codes in the PGA.
0x1D
Read/Write
[7:0]
00001000
Slew Limit
Limits the amount the offset can change by in a single update.
0x1E Read/Write
[7:0]
32
Sync Filter Lock
Threshold
Number of clean Hsyncs required for sync filter to lock.
0x1F Read/Write
[7:0]
50
Sync Filter Unlock
Threshold
Number of missing Hsyncs required to unlock the sync filter. Counter
counts up if Hsync pulse is missing and down for a good Hsync.
0x20 Read/Write
[7:0]
50
Sync Filter Window
Width
Width of the window in which Hsync pulses are allowed.
0x21
Read/Write
[7]
1*******
SP Sync Filter Enable
Enables Coast, Vsync duration, and Vsync filter to use the
regenerated Hsync rather than the raw Hsync.
AD9880
Rev. 0 | Page 26 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
[6]
*1******
PLL Sync Filter Enable
Enables the PLL to use the filtered Hsync rather than the raw
Hsync. This clips any bad Hsyncs, but does not regenerate
missing pulses.
[5]
**0*****
Vsync Filter Enable
Enables the Vsync filter. The Vsync filter gives a predictable
Hsync/Vsync timing relationship but clips one Hsync period off
the leading edge of Vsync.
[4]
***0****
Vsync Duration
Enable
Enables the Vsync duration block. This block can be used if
necessary to restore the duration of a filtered Vsync.
[3]
****
1***
Auto Offset Clamp
Mode
0 = auto offset measures code during clamp.
1 = auto offset measures code (10 or 16) clock cycles after end of
clamp for 6 clock cycles.
[2]
****
*1**
Auto Offset Clamp
Length
Sets delay after end of clamp for auto offset clamp mode = 1.
0 = Delay is 10 clock cycles.
1 = Delay is 16 clock cycles.
0x22
Read/Write
[7:0]
4
Vsync Duration
Vsync Duration.
0x23 Read/Write
[7:0]
32
Hsync
Duration Hsync Duration. Sets the duration of the output Hsync in pixel
clocks.
0x24 Read/Write
[7]
1*******
Hsync Output
Polarity
Output Hsync Polarity (both DVI and Analog). 0 = active low out.
1 = active high out.
[6]
*1******
Vsync Output Polarity
Output Vsync polarity (both DVI and analog).
0 = active low out.
1 = active high out.
[5]
**1*****
DE Output Polarity
Output DE polarity (both DVI and analog) .
0 = active low out.
1 = active high out.
[4]
***1****
Field Output Polarity
Output field polarity (both DVI and analog).
0 = active low out.
1 = active high out.
[3]
****1***
SOG Output Polarity
Output SOG polarity (analog only).
0 = active low out.
1 = active high out.
[2:1]
*****11*
SOG Output Select
Selects signal present on SOG output.
00 = SOG (SOG0 or SOG1).
01 = Raw Hsync (HSYNC0 or HSYNC1).
10 = Regenerated sync.
11 = Hsync to PLL.
[0]
*******0
Output CLK Invert
0 = Don't invert clock out.
1 = Invert clock out.
0x25
Read/Write
[7:6]
01******
Output CLK Select
Select which clock to use on output pin. 1 CLK is divided down
from TMDS clock input when pixel repetition is in use.
00 = CLK.
01 = 1 CLK.
10 = 2 CLK.
11 = 90 phase 1X CLK.
[5:4]
**11****
Output Drive
Strength
Set the drive strength of the outputs.
00 = lowest, 11 = highest.
[3:2]
****00**
Output Mode
Selects which pins the data comes out on.
00 = 4:4:4 mode (normal).
01 = 4:2:2 + DDR 4:2:2 on blue.
10 = DDR 4:4:4 + DDR 4:2:2 on blue.
AD9880
Rev. 0 | Page 27 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
11 = 12-bit 4:2:2 (HDMI can have 12-bit 4:2:2 data).
[1]
******1*
Primary Output
Enable
Enables primary output.
[0]
*******0
Secondary Output
Enable
Enables secondary output (DDR 4:2:2 in Output Modes 1 and 2).
0x26
Read/Write
[7]
0*******
Output Three-State
Three-state the outputs.
[6]
*0******
SOG Three-State
Three-state the SOG output.
[5]
**0*****
SPDIF Three-State
Three-state the SPDIF output.
[4]
***0****
I2S Three-State
Three-state the I2S output and the MCLK out.
[3]
****1***
Power-Down Pin
Polarity
Sets polarity of power-down pin.
0 = active low.
1 = active high.
Selects the function of the power-down pin.
[2:1]
*****00*
Power-Down Pin
Function
00 = power-down.
01 = power-down and three-state SOG.
10 = three-state outputs only.
11 = three-state outputs and SOG.
[0]
*******0
Power-Down
0 = normal.
1 = power-down.
0x27 Read/Write
[7]
1*******
Auto Power-Down
Enable
0 = disable auto low power state.
1 = enable auto low power state.
[6]
*0******
HDCP
A0
Sets the LSB of the address of the HDCP I
2
C. Set to 1 only for a
second receiver in a dual-link configuration.
0 = Use internally generated MCLK.
1 = Use external MCLK input.
[5]
**0*****
MCLK External
Enable
If an external MCLK is used then it must be locked to the video
clock according to the CTS and N available in the I
2
C. Any mis-
match between the internal MCLK and the input MCLK results in
dropped or repeated audio samples.
[4]
***0****
BT656
EN
Enables EAV/SAV codes to be inserted into the video output
data.
[3]
****0***
Force DE Generation
Allows use of the internal DE generator in DVI mode.
[2:0]
*****000
Interlace
Offset
Sets the difference (in Hsyncs) in field length between Field 0
and Field 1.
0x28 Read/Write
[7:2]
011000**
VS
Delay
Sets the delay (in lines) from Vsync leading edge to the start of
active video.
[1:0]
******01
HS Delay MSB
MSB, Register 0x29.
0x29 Read/Write
[7:0]
00000100
HS
Delay
Sets the delay (in pixels) from Hsync leading edge to the start of
active video.
0x2A
Read/Write
[3:0]
****0101
Line Width MSB
MSB, Register 0x2B.
0x2B
Read/Write
[7:0]
00000000
Line Width
Sets the width of the active video line (in pixels).
0x2C
Read/Write
[3:0]
****0010
Screen Height MSB
MSB, Register 0x2D.
0x2D
Read/Write
[7:0]
11010000
Screen Height
Sets the height of the active screen (in lines).
0x2E
Read/Write
[7]
0*******
Ctrl EN
Allows Ctrl [3:0] to be output on the I2s data pins.
00 = I2S mode.
[6:5]
*00*****
I2S Out Mode
01 = right-justified.
10 = left-justified.
11 = raw IEC60958 mode.
[4:0]
***11000
I2S Bit Width
Sets the desired bit width for right-justified mode.
AD9880
Rev. 0 | Page 28 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0x2F
Read
[6]
*0******
TMDS Sync Detect
Detects a TMDS DE.
[5]
**0*****
TMDS Active
Detects a TMDS clock.
[4]
***0****
AV Mute
Gives the status of AV mute based on general control packets.
[3]
****0***
HDCP Keys Read
Returns 1 when read of EEPROM keys is successful.
[2:0]
*****000
HDMI Quality
Returns quality number based on DE edges.
0x30 Read
[6]
*0******
HDMI Content
Encrypted
This bit is high when HDCP decryption is in use (content is
protected). The signal goes low when HDCP is not being used.
Customers can use this bit to determine whether or not to allow
copying of the content. The bit should be sampled at regular
intervals since it can change on a frame by frame basis.
[5]
**0*****
DVI Hsync Polarity
Returns DVI Hsync polarity.
[4]
***0****
DVI Vsync Polarity
Returns DVI Vsync polarity.
[3:0]
****0000
HDMI Pixel
Repetition
Returns current HDMI pixel repetition amount. 0 = 1, 1 = 2, ...
The clock and data outputs automatically de-repeat by this
value.
0x31
Read/Write
[7:4]
1001****
MV Pulse Max
Sets the max pseudo sync pulse width for Macrovision
detection.
[3:0]
****0110
MV Pulse Min
Sets the min pseudo sync pulse width for Macrovision detection.
0x32 Read/Write
[7]
0*******
MV
Oversample
En
Tells the Macrovision detection engine whether we are
oversampling or not.
[6]
*0******
MV Pal En
Tells the Macrovision detection engine to enter PAL mode.
[5:0]
**001101
MV Line Count Start
Sets the start line for Macrovision detection.
0x33
Read/Write
[7]
1*******
MV Detect Mode
0 = standard definition.
1 = progressive scan mode.
[6]
*0******
MV Settings Override
0 = use hard coded settings for line counts and pulse widths.
1 = use I
2
C values for these settings.
[5:0]
**010101
MV Line Count End
Sets the end line for Macrovision detection.
0x34
Read/Write
[7:6]
10******
MV Pulse Limit Set
Sets the number of pulses required in the last 3 lines (SD mode
only).
[5]
**0*****
Low Freq Mode
Sets whether the Audio PLL is in low freq. mode or not. Low
frequency mode should only be set for pixel clocks <80 MHz.
[4]
***0****
Low
Freq
Override
Allows the previous bit to be used to set low frequency mode
rather than the internal auto-detect.
[3]
****0***
Up Conversion Mode
0 = Repeat Cr and Cb values.
1 = Interpolate Cr and Cb values.
[2]
*****0**
CrCb Filter Enable
Enables the FIR filter for 4:2:2 CrCb output.
[1]
******0*
CSC_Enable Enables the color space converter (CSC). The default settings for
the CSC provide HDTV to RGB conversion.
Sets the fixed point position of the CSC coefficients. Including
the A4, B4, C4, offsets.
0x35
Read/Write
[6:5]
*01* ****
CSC_Mode
00 = 1.0, -4096 to 4095
01 =2.0, -8192 to 8190
1 = 4.0, -16384 to 16380
[4:0]
***01100
CSC_Coeff_A1 MSB
MSB, Register 0x36.
0x36
Read/Write
[7:0]
01010010
CSC_Coeff_A1
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x37
Read/Write
[4:0]
***01000
CSC_Coeff_A2 MSB
MSB, Register 0x38.
0x38
Read/Write
[7:0]
00000000
CSC_Coeff_A2
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
+ (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
AD9880
Rev. 0 | Page 29 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0x39
Read/Write
[4:0]
***00000
CSC_Coeff_A3 MSB
MSB, Register 0x3A.
0x3A
Read/Write
[7:0]
00000000
CSC_Coeff_A3
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x3B
Read/Write
[4:0]
***11001
CSC_Coeff_A4 MSB
MSB, Register 0x3C.
0x3C
Read/Write
[7:0]
11010111
CSC_Coeff_A4
Color space Converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x3D
Read/Write
[4:0]
***11100
CSC_Coeff_B1 MSB
MSB, Register 0x3E.
0x3E
Read/Write
[7:0]
01010100
CSC_Coeff_B1
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x3F
Read/Write
[4:0]
***01000
CSC_Coeff_B2 MSB
MSB, Register 0x40.
0x40
Read/Write
[7:0]
00000000
CSC_Coeff_B2
Color space Converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x41
Read/Write
[4:0]
***11110
CSC_Coeff_B3 MSB
MSB, Register 0x42.
0x42
Read/Write
[7:0]
10001001
CSC_Coeff_B3
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
+ (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x43
Read/Write
[4:0]
***00010
CSC_Coeff_B4 MSB
MSB, Register 0x44.
0x44
Read/Write
[7:0]
10010010
CSC_Coeff_B4
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 R
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x45
Read/Write
[4:0]
***00000
CSC_Coeff_C1 MSB
MSB, Register 0x46.
0x46
Read/Write
[7:0]
00000000
CSC_Coeff_C1
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x47
Read/Write
[4:0]
***01000
CSC_Coeff_C2 MSB
MSB, Register 0x48.
0x48
Read/Write
[7:0]
00000000
CSC_Coeff_C2
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x49
Read/Write
[4:0]
***01110
CSC_Coeff_C3 MSB
MSB, Register 0x4A.
0x4A
Read/Write
[7:0]
10000111
CSC_Coeff_C3
Color space converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
0x4B
Read/Write
[4:0]
***11000
CSC_Coeff_C4 MSB
MSB, Register 0x4C.
0x4C
Read/Write
[7:0]
10111101
CSC_Coeff_C4
Color space Converter (CSC) coefficient for equation:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
AD9880
Rev. 0 | Page 30 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0x50
Read/Write
[7:0]
00100000
Test
Must be written to 0x20 for proper operation.
0x56
Read/Write
[7:0]
00001111
Test
Must be written to default 0x0F for proper operation.
0x57
Read/Write
[7]
0*******
A/V Mute Override
A1 overrides the AV mute value with Bit 6.
[6]
*0******
AV Mute Value
Sets AV mute value if override is enabled.
[3]
****0***
Disable Video Mute
Disables mute of video during AV mute.
[2]
*****0**
Disable Audio Mute
Disables mute of audio during AV mute.
0x58 Read/Write
[7]
MCLK
PLL
Enable
MCLK PLL enable--uses analog PLL.
[6:4]
MCLK
PLL_N MCLK PLL N [2:0]--this controls the division of the MCLK out of
the PLL: 0 = /1, 1 = /2, 2 = /3, 3 = /4, etc.
[3]
N_CTS_Disable
Prevents the N/CTS packet on the link from writing to the N and
CTS registers.
[2:0]
MCLK
FS_N Controls the multiple of 128 fs used for MCLK out . 0 = 128 fs,
1 = 256 fs, 2 = 384, 7 = 1024 fs.
0x59
Read/Write
[6]
MDA/MCL PU
This disables the MDA/MCL pull-ups.
[5]
CLK Term O/R
Clock termination power-down override 0 = auto, 1 = manual.
[4]
Manual CLK Term
Clock termination: 0 = normal, 1 = disconnected.
[2]
FIFO Reset UF
This bit resets the audio FIFO if underflow is detected.
[1]
FIFO Reset OF
This bit resets the audio FIFO if overflow is detected.
[0]
MDA/MCL Three-
State
This bit three-states the MDA/MCL lines.
0x5A Read
[6:0]
Packet
Detected These 7 bits are updated if any specific packet has been received
since last reset or loss of clock detect. Normal is 0x00.
Bit Data Packet Detected
0
AVI
infoframe.
1
Audio
infoframe.
2
SPD
infoframe.
3
MPEG source infoframe.
4
ACP
packets.
5
ISRC1
packets.
6
ISRC2
packets.
0x5B
Read
[3]
HDMI Mode
0 = DVI, 1 = HDMI.
0x5E
Read
[7:6]
Channel Status
Mode = 00. All others are reserved.
[5:3]
When Bit 1 = 0 (Linear PCM).
000 = 2 audio channels without pre-emphasis.
001 = 2 audio channels with 50/15 s pre-emphasis.
010 = reserved.
011 = reserved.
2
0 = Software for which copyright is asserted.
1 = Software for which no copyright is asserted.
1
0 = audio sample word represents linear PCM samples.
1 = audio sample word used for other purposes.
0
0 = consumer use of channel status block.
Audio Channel Status
0x5F Read
[7:0]
Channel Status
Category Code
0x60 Read
[7:4]
Channel
Number
[3:0]
Source
Number
0x61
Read
[5:4]
Clock Accuracy
Clock accuracy.
00
=
Level
II.
01
=
Level
III.
10
=
Level
I.
11
=
reserved.
[3:0]
Sampling
0011
=
32
kHz.
AD9880
Rev. 0 | Page 31 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
Frequency 0000
=
44.1
kHz.
1000
=
88.2
kHz.
1100
=
176.4
kHz.
0010
=
48k
Hz.
1010
=
96
kHz.
1110
=
192
kHz.
0x62
Read
[3:0]
Word Length
Word length.
0000
not
specified.
0100
16
bits.
0011
17
bits.
0010
18
bits.
0001
19
bits.
0101
20
bits.
1000
not
specified.
1100
20
bits.
1011
21
bits.
1010
22
bits.
1001
23
bits.
1101
24
bits.
0x7B Read
[7:0]
CTS
[19:12]
Cycle time stamp--this 20-bit value is used with the N value to
regenerate an audio clock. For remaining bits see Register 0x7C
and Register 0x7D.
0x7C Read
[7:0]
CTS
[11:4]
0x7D Read
[7:4]
CTS
[3:0]
Read [3:0]
N
[19:16]
20-bit N used with CTS to regenerate the audio clock. For
remaining bits, see Register 0x7E and Register 0x7F.
0x7E Read
[7:0]
N
[15:8]
0x7F Read
[7:0]
N
[7:0]
AVI Infoframe
0x80 Read
[7:0]
AVI
Infoframe
Version
0x81
Read
[6:5]
Y [1:0] Indicates RGB, 4:2:2 or 4:4:4.
00
=
RGB.
01
=
YCbCr
4:2:2.
10
=
YCbCr
4:4:4.
4
Active Format
Active format information present.
Information Status
0
= no data.
1
= active format information valid.
[3:2]
Bar Information
B [1:0].
00 = no bar information.
01 = horizontal bar information valid.
10 = vertical bar information valid.
11 = horizontal and vertical bar information valid.
[1:0]
Scan Information
S [1:0].
00
=
no
information.
01
=
overscanned
(television).
10
=
underscanned
(computer).
0x82 Read
[7:6]
Colorimetry
C
[1:0].
00
=
no
data.
01
= SMPTE 170M, ITU601.
10
=
ITU709.
[5:4]
Picture Aspect Ratio
M [1:0].
00
=
no
data.
AD9880
Rev. 0 | Page 32 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
01
=
4:3.
10
=
16:9.
[3:0]
Active Format Aspect
Ratio
R [3:0].
1000 =
same as picture aspect ratio.
1001
=
4:3
(center).
1010
=
16:9
(center).
1011
=
14:9
(center).
0x83 Read
[1:0]
Nonuniform Picture
Scaling
SC[1:0].
00
= no known non-uniform scaling.
01
= picture has been scaled horizontally.
10
= picture has been scaled vertically.
11
= picture has been scaled horizontally and vertically.
0x84 Read
[6:0]
Video Identification
Code
VIC [6:0] video identification code--refer to CEA EDID short
video descriptors.
0x85 Read
[3:0]
Pixel
Repeat
PR [3:0]--This specifies how many times a pixel has been
repeated.
0000 =
no repetition--pixel sent once.
0001 =
pixel sent twice (repeated once).
0010 =
pixel sent 3 times.
1001 =
pixel sent 10 times.
0xA--0xF
reserved.
0x86
Read
[7:0]
Active Line Start LSB
This represents the line number of the end of the top horizontal
bar. If 0, there is no horizontal bar. Combines with Register 0x88
for a 16 bit value.
0x87
Read
[6:0]
New Data Flags
New data flags. These 8 bits are updated if any specific data
changes. Normal (no NDFs) is 0x00. When any NDF register is
read, all bits reset to 0x00. All NDF registers contain the same
data.
Bit Data Packet Changed
0
AVI
Infoframe.
1
audio
Infoframe.
2
SPD
Infoframe.
3
MPEG source Infoframe.
4
ACP
packets.
5
ISRC1
packets.
6
ISRC2
packets.
0x88
Read
[7:0]
Active Line Start MSB
Active line start MSB (see Register 0x86).
0x89
Read
[7:0]
Active Line End LSB
This represents the line number of the beginning of a lower
horizontal bar. If greater than the number of active video lines,
there is no lower horizontal bar. Combines with Register 0x8A
for a 16-bit value.
0x8A
Read
[7:0]
Active Line End MSB
Active line end MSB. See Register 0x89.
0x8B
Read
[7:0]
Active Pixel Start LSB
This represents the last pixel in a vertical pillar-bar at the left side
of the picture. If 0, there is no left bar. Combines with Register
0x8C for a 16-bit value.
0x8C
Read
[7:0]
Active Pixel Start MSB
Active pixel start MSB. See Register 0x8B.
0x8D
Read
[7:0]
Active Pixel End LSB
This represents the first horizontal pixel in a vertical pillar-bar at
the right side of the picture. If greater than the maximum
number of horizontal pixels, there is no vertical bar. Combines
with Register 0x8E for a16-bit value.
0x8E
Read
[7:0]
Active Pixel End MSB
Active pixel end MSB. See Register 0x8D.
0x8F
Read
[6:0]
New Data Flags
New Data Flags (see 0x87).
AD9880
Rev. 0 | Page 33 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0x90 Read
[7:0]
Audio Infoframe
Version
0x91
Read
[7:4]
Audio Coding Type
CT [3:0]. Audio coding type.
0x00
=
Refer to stream header.
0x01
=
IEC60958
PCM.
0x02
=
AC3.
0x03
=
MPEG1 (Layers 1 and 2).
0x04
=
MP3 (MPEG1 Layer 3).
0x05
=
MPEG2
(multichannel).
0x06
=
AAC.
0x07
=
DTS.
0x08
=
ATRAC.
[2:0]
Audio Coding Count
CC [2:0]. Audio channel count.
000 = refer to stream header.
001
=
2
channels.
010
=
3
channels.
111
=
8
channels
0x92
Read
[4:2]
Sampling Frequency
SF [2:0]. Sampling frequency.
000 = refer to stream header.
001
=
32
kHz.
010 = 44.1 kHz (CD).
011
=
48
kHz.
100
=
88.2
kHz.
101
=
96
kHz.
110
=
176.4
kHz.
111
=
192
kHz.
[1:0]
Sample Size
SS [1:0]. Sample size.
00
= refer to stream header.
01
=
16
bit.
10
=
20
bit.
11
=
24
bit.
0x93
Read
[7:0]
Max Bit Rate
Max bit rate (compressed audio only).The value of this field
multiplied by 8 kHz represents the maximum bit rate.
0x94 Read
[7:0]
Speaker
Mapping CA [7:0]. Speaker mapping or placement for up to 8 channels.
See table 91 in detailed description.
7
Down-Mix DM_INH--down-mix
inhibit.
0 = permitted or no information.
1
=
prohibited.
0x95
Read
[6:3]
Level Shift
LSV [3:0]--level shift values with attenuation information.
0000 =
0 dB attenuation.
0001 =
1 dB attenuation.
.....
1111 =
15 dB attenuation.
0x96 Read
[7:0]
Reserved.
0x97
Read
[6:0]
New Data Flags
New data flags (see 0x87).
Source Product Description (SPD) Infoframe
0x98 Read
[7:0]
Source Product
Description (SPD)
Infoframe Version
0x99 Read
[7:0]
Vender Name
Character 1
Vender name character 1 (VN1) (7-bit ASCII code)--This is the
first character in 8 that is the name of the company that appears
on the product.
AD9880
Rev. 0 | Page 34 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0x9A Read
[7:0]
VN2
VN2.
0x9B Read
[7:0]
VN3
VN3.
0x9C Read
[7:0]
VN4
VN4.
0x9D Read
[7:0]
VN5
VN5.
0x9E Read
[7:0]
VN6
VN6.
0x9F
Read
[6:0]
New Data Flags
New data flags (see 0x87).
0xA0 Read
[7:0]
VN7
VN7.
0xA1 Read
[7:0]
VN8
VN8.
0xA2 Read
[7:0]
Product Description
Character 1
Product Description Character 1 (PD1) (7-bit ASCII code)--This is
the first character of 16 that contains the model number and a
short description.
0xA3 Read
[7:0]
PD2
PD2.
0xA4 Read
[7:0]
PD3
PD3.
0xA5 Read
[7:0]
PD4
PD4.
0xA6 Read
[7:0]
PD5
PD5.
0xA7
Read
[7:0]
New Data Flags
New data flags (see 0x87).
0xA8 Read
[6:0]
PD6
PD6.
0xA9 Read
[7:0]
PD7
PD7.
0xAA Read
[7:0]
PD8
PD8.
0xAB Read
[7:0]
PD9
PD9.
0xAC Read
[7:0]
PD10
PD10.
0xAD Read
[7:0]
PD11
PD11.
0xAE Read
[7:0]
PD12
PD12.
0xAF
Read
[6:0]
New Data Flags
New data flags (see 0x87).
0xB0 Read
[7:0]
PD13
PD13.
0xB1 Read
[7:0]
PD14
PD14.
0xB2 Read
[7:0]
PD15
PD15.
0xB3 Read
[7:0]
PD16
PD16.
0xB4
Read
[7:0]
Source Device
This is a code that classifies the source device.
Information
Code
0x00
=
unknown.
0x01
=
Digital
STB.
0x02
=
DVD.
0x03
=
D-VHS.
0x04
=
HDD
video.
0x05
=
DVC.
0x06
=
DSC.
0x07
=
Video
CD.
0x08
=
Game.
0x09
=
PC
general.
0xB7
Read
[6:0]
New Data Flags
New data flags (see 0x87).
MPEG Source Infoframe
0xB8 Read
[7:0]
MPEG Source
Infoframe Version
0xB9 Read
[7:0]
MB(0)
MB [0] (Lower byte of MPEG bit rate: Hz) This is the lower 8 bits of
32 bits (4 bytes) that specify the MPEG bit rate in Hz.
0xBA Read
[7:0]
MB[1]
MB
[1].
0xBB Read
[7:0]
MB[2]
MB
[2].
0xBC
Read
[7:0]
MB [3] (upper byte).
4
Field Repeat
FR--New field or repeated field.
0 = New field or picture.
1 = Repeated field.
AD9880
Rev. 0 | Page 35 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0xBD
Read
[1:0]
MPEG Frame
MF [1:0] This identifies whether frame is an I, B, or P picture.
00
=
unknown.
01
=
I
picture.
10
=
B
picture.
11
=
P
picture.
0xBE Read
[7:0]
Reserved.
0xBF
Read
[6:0]
New Data Flags
New data flags (see 0x87).
0xC0
Read
[7:0]
Audio content protection packet (ACP) type.
0x00
=
Generic
audio.
0x01
=
IEC 60958-identified audio.
0x02
=
DVD-audio.
0x03
=
Reserved for super audio CD (SACD).
Audio Content
Protection Packet
(ACP) Type
0x04 0xFF
reserved.
0xC1
Read
[7:0]
ACP Packet Byte 0
ACP Packet Byte 0 (ACP_PB0).
0xC2 Read
[7:0]
ACP_PB1
ACP_PB1.
0xC3 Read
[7:0]
ACP_PB2
ACP_PB2.
0xC4 Read
[7:0]
ACP_PB3
ACP_PB3.
0xC5 Rea
[7:0]
ACP_PB4
ACP_PB4.
0xC6 Read
[7:0]
ACP_PB5
ACP_PB5.
0xC7
Read
[6:0]
NDF
New data flags (see 0x87).
0xC8
7
ISRC1
Continued International standard recording code (ISRC1) continued--This
indicates an ISRC2 packet is being transmitted.
Read
6
ISRC1 Valid
0 = ISRC1 status BITS and PBs not valid.
1 = ISRC1 status BITS and PBs valid.
001 = starting position.
[2:0]
ISRC1 Status
010 = intermediate position.
100
=
final
position.
0xC9
Read
[7:0]
ISRC1 Packet Byte 0
ISRC1 Packet Byte 0 (ISRC1_PB0).
0xCA Read
[7:0]
ISRC1_PB1
ISRC1_PB1.
0xCB Read
[7:0]
ISRC1_PB2
ISRC1_PB2.
0xCC Read
[7:0]
ISRC1_PB3
ISRC1_PB3.
0xCD Read
[7:0]
ISRC1_PB4
ISRC1_PB4.
0xCE Read
[7:0]
ISRC1_PB5
ISRC1_PB5.
0xCF
Read
[6:0]
NDF
New data flags (see 0x87).
0xD0 Read
[7:0]
ISRC1_PB6
ISRC1_PB6.
0xD1 Read
[7:0]
ISRC1_PB7
ISRC1_PB7.
0xD2 Read
[7:0]
ISRC1_PB8
ISRC1_PB8.
0xD3 Read
[7:0]
ISRC1_PB9
ISRC1_PB9.
0xD4 Read
[7:0]
ISRC1_PB10
ISRC1_PB10.
0xD5 Read
[7:0]
ISRC1_PB11
ISRC1_PB11.
0xD6 Read
[7:0]
ISRC1_PB12
ISRC1_PB12.
0xD7
Read
[6:0]
NDF
New data flags (see 0x87).
0xD8 Read
[7:0]
ISRC1_PB13
ISRC1_PB13.
0xD9 Read
[7:0]
ISRC1_PB14
ISRC1_PB14.
0xDA Read
[7:0]
ISRC1_PB15
ISRC1_PB15.
0xDB Read
[7:0]
ISRC1_PB16
ISRC1_PB16.
0xDC
Read
[7:0]
ISRC2 Packet Byte 0
ISRC2 Packet Byte 0 (ISRC2_PB0)--This is transmitted only when
the ISRC_ continue bit (Register 0xC8, Bit 7) is set to 1.
0xDD Read
[7:0]
ISRC2_PB1
ISRC2_PB1.
0xDE Read
[7:0]
ISRC2_PB2
ISRC2_PB2.
0xDF
Read
[6:0]
New Data Flags
New data flags (see 0x87).
AD9880
Rev. 0 | Page 36 of 64
Hex
Address
Read/Write
or Read Only
Bits
Default
Value Register
Name Description
0xE0 Read
[7:0]
ISRC2_PB3
ISRC2_PB3.
0xE1 Read
[7:0]
ISRC2_PB4
ISRC2_PB4.
0xE2 Read
[7:0]
ISRC2_PB5
ISRC2_PB5.
0xE3 Read
[7:0]
ISRC2_PB6
ISRC2_PB6.
0xE4 Read
[7:0]
ISRC2_PB7
ISRC2_PB7.
0xE5 Read
[7:0]
ISRC2_PB8
ISRC2_PB8.
0xE6 Read
[7:0]
ISRC2_PB9
ISRC2_PB9.
0xE7
Read
[6:0]
New Data Flags
New data flags (see 0x87).
0xE8 Read
[7:0]
ISRC2_PB10
ISRC2_PB10.
0xE9 Read
[7:0]
ISRC2_PB11
ISRC2_PB11.
0xEA Read
[7:0]
ISRC2_PB12
ISRC2_PB12.
0xEB Read
[7:0]
ISRC2_PB13
ISRC2_PB13.
0xEC Read
[7:0]
ISRC2_PB14
ISRC2_PB14.
0xED
Read
[7:0]
ISRC2_PB15
ISRC2_PB15.
0xEE Read
[7:0]
ISRC2_PB16
ISRC2_PB16.
AD9880
Rev. 0 | Page 37 of 64
2-WIRE SERIAL CONTROL REGISTER DETAIL
CHIP IDENTIFICATION
0x00 7-0 Chip
Revision
An 8-bit value that reflects the current chip revision.
PLL DIVIDER CONTROL
0x01
7-0
PLL Divide Ratio MSBs
The eight most significant bits of the 12-bit PLL divide
ratio PLLDIV.
The PLL derives a pixel clock from the incoming
Hsync signal. The pixel clock frequency is then
divided by an integer value, such that the output is
phase-locked to Hsync. This PLLDIV value
determines the number of pixel times (pixels plus
horizontal blanking overhead) per line. This is
typically 20% to 30% more than the number of active
pixels in the display.
The 12-bit value of the PLL divider supports divide
ratios from 221 to 4095. The higher the value loaded
in this register, the higher the resulting clock
frequency with respect to a fixed Hsync frequency.
VESA has established some standard timing
specifications, which assists in determining the value
for PLLDIV as a function of horizontal and vertical
display resolution and frame rate (see Table 8).
However, many computer systems do not conform
precisely to the recommendations, and these numbers
should be used only as a guide. The display system
manufacturer should provide automatic or manual
means for optimizing PLLDIV. An incorrectly set
PLLDIV usually produces one or more vertical noise
bars on the display. The greater the error, the greater
the number of bars produced.
The power-up default value of PLLDIV is 1693
(PLLDIVM = 0x69, PLLDIVL = 0xDx)
The AD9880 updates the full divide ratio only when
the LSBs are changed. Writing to this register by itself
does not trigger an update.
0x02
7-4
PLL Divide Ratio LSBs
The four least significant bits of the 12-bit PLL divide
ratio PLLDIV.
The power-up default value of PLLDIV is 1693
(PLLDIVM = 0x69, PLLDIVL = 0xDx).
CLOCK GENERATOR CONTROL
0x03
7-6
VCO Range Select
Two bits that establish the operating range of the clock
generator. VCORNGE must be set to correspond with
the desired operating frequency (incoming pixel rate).
The PLL gives the best jitter performance at high fre-
quencies. For this reason, to output low pixel rates and
still get good jitter performance, the PLL actually
operates at a higher frequency but then divides down
the clock rate. Table 12 shows the pixel rates for each
VCO range setting. The PLL output divisor is auto-
matically selected with the VCO range setting.
Table 12. VCO Ranges
VCO Range
Pixel Rate Range
00
12 to 30
01
30 to 60
10
60 to 120
11
120 to 150
The power-up default value is 01.
5-3 Charge
Pump
Current
Three bits that establish the current driving the loop
filter in the clock generator.
Table 13. Charge Pump Currents
Ip2 Ip1 Ip0 Current
(A)
0 0 0 50
0 0 1 100
0 1 0 150
0 1 1 250
1 0 0 350
1 0 1 500
1 1 0 750
1 1 1 1500
The power-up default value is current = 001.
2
External Clock Enable
This bit determines the source of the pixel clock.
Table 14. External Clock Select Settings
EXTCLK Function
0
Internally generated clock.
1
Externally provided clock signal
A Logic 0 enables the internal PLL that generates the
pixel clock from an externally provided Hsync.
A Logic 1 enables the external CKEXT input pin. In
this mode, the PLL divide ratio (PLLDIV) is ignored.
The clock phase adjusts (phase is still functional). The
power-up default value is EXTCLK = 0.
AD9880
Rev. 0 | Page 38 of 64
0x04 7-3
Phase
Adjust
These bits provide a phase adjustment for the DLL to
generate the ADC clock. A 5-bit value that adjusts the
sampling phase in 32 steps across one pixel time. Each
step represents an 11.25 shift in sampling phase. The
power up default is 16.
INPUT GAIN
0x05 7-0 Red
Channel
Gain
These bits control the programmable gain amplifier
(PGA) of the red channel. The AD9880 can accom-
modate input signals with a full-scale range of
between 0.5 V and 1.0 V p-p. Setting the red gain to
255 corresponds to an input range of 1.0 V. A red gain
of 0 establishes an input range of 0.5 V. Note that
increasing red gain results in the picture having less
contrast (the input signal uses fewer of the available
converter codes). The power-up default is 0x80.
0x06
7-0
Green Channel Gain
These bits control the PGA of the green channel. The
AD9880 can accommodate input signals with a full-
scale range of between 0.5 V and 1.0 V p-p. Setting the
green gain to 255 corresponds to an input range of 1.0
V. A green gain of 0 establishes an input range of 0.5 V.
Note that increasing green gain results in the picture
having less contrast (the input signal uses fewer of the
available converter codes). The power-up default is
0x80.
0x07 7-0 Blue
Channel
Gain
These bits control the PGA of the blue channel. The
AD9880 can accommodate input signals with a full-
scale range of between 0.5 V and 1.0 V p-p. Setting the
blue gain to 255 corresponds to an input range of
1.0 V. A blue gain of 0 establishes an input range of
0.5 V. Note that increasing blue gain results in the
picture having less contrast (the input signal uses
fewer of the available converter codes). The power-up
default is 0x80.
INPUT OFFSET
0x08
7-0
Red Channel Offset Adjust
If clamp feedback is enabled, the 8-bit offset adjust
determines the clamp code. The 8-bit offset adjust is a
twos complement number consisting of 1 sign bit plus
7 bits (0x7F = +127, 0x00 = 0, 0xFF = -1, and 0x80 =
-128). For example, if the register is programmed to
130d, then the output code is equal to 130d at the end
of the clamp period. Note that incrementing the offset
register setting by 1 LSB adds 1 LSB of offset,
regardless of the clamp feedback setting.
The power-up default is 0.
0x09 7-0 Red
Channel
Offset
These eights bits are the red channel offset control.
The offset control shifts the analog input, resulting in
a change in brightness. Note that the function of the
offset register depends on whether clamp feedback is
enabled (Register 0x1C, Bit 7 = 1).
If clamp feedback is disabled, the offset register bits
control the absolute offset added to the channel. The
offset control provides a +127/-128 LSBs of adjust-
ment range, with one LSB of offset corresponding to
1 LSB of output code. If clamp feedback is enabled
these bits provide the relative offset (brightness) from
the offset adjust in the previous register. The power-up
default is 0x80.
0x0A 7-0 Green
Channel Offset Adjust
If clamp feedback is enabled, the 8-bit offset adjust
determines the clamp code. The 8-bit offset adjust is a
twos complement number consisting of 1 sign bit plus
7 bits (0x7F = +127, 0x00 = 0, 0xFF = -1, and 0x80 =
-128). For example, if the register is programmed to
130d, then the output code is equal to 130d at the end
of the clamp period. Note that incrementing the offset
register setting by 1 LSB adds 1 LSB of offset, regard-
less of the clamp feedback setting. The power-up
default is 0.
0x0B
7-0
Green Channel Offset
These eight bits are the green channel offset control.
The offset control shifts the analog input, resulting in
a change in brightness. Note that the function of the
offset register depends on whether clamp feedback is
enabled (Register 0x1C, Bit 7 = 1).
If clamp feedback is disabled, the offset register bits
control the absolute offset added to the channel. The
offset control provides a +127/-128 LSBs of adjust-
ment range, with one LSB of offset corresponding to
1 LSB of output code. If clamp feedback is enabled
these bits provide the relative offset (brightness) from
the offset adjust in the previous register. The power-up
default is 0x80.
0x0C
7-0
Blue Channel Offset Adjust
If clamp feedback is enabled, the 8-bit offset adjust
determines the clamp code. The 8-bit offset adjust is a
twos complement number consisting of 1 sign bit plus
7 bits (0x7F = +127, 0x00 = 0, 0xFF = -1, and 0x80 =
-128). For example, if the register is programmed to
130d, then the output code is equal to 130d at the end
of the clamp period. Note that incrementing the offset
register setting by 1 LSB adds 1 LSB of offset, regard-
less of the clamp feedback setting. The power-up
default is 0.
AD9880
Rev. 0 | Page 39 of 64
0x0D 7-0
Blue
Channel
Offset
These eight bits are the blue channel offset control.
The offset control shifts the analog input, resulting in
a change in brightness. Note that the function of the
offset register depends on whether clamp feedback is
enabled (Register 0x1C, Bit 7 = 1).
If clamp feedback is disabled, the offset register bits
control the absolute offset added to the channel. The
offset control provides a +127/-128 LSBs of adjust-
ment range, with 1 LSB of offset corresponding to
1 LSB of output code. If clamp feedback is enabled
these bits provide the relative offset (brightness) from
the offset adjust in the previous register. The power-up
default is 0x80.
SYNC
0x0E 7-0 Sync
Separator
Selects the max Hsync pulse width for composite sync
separation. Power-down default is 0x20.
0x0F
7-2
SOG Comparator Threshold Enter
The enter level for the SOG slicer. Must be < than exit
level (Register 0x10). The power-up default is 0x10.
0x10
7-2
SOG Comparator Threshold Exit
The exit level for the SOG slicer. Must be > enter level
(Register 0x0F). The power-up default is 0x10.
0x11 7
Hsync
Source
0 = Hsync, 1 = SOG. The power-up default is 0. These
selections are ignored if Register 0x11, Bit 6 = 0.
0x11 6
Hsync
Source
Override
0 = auto Hsync source, 1 = manual Hsync source.
Manual Hsync source is defined in Register 0x11,
Bit 7. The power-up default is 0.
0x11 5
Vsync
Source
0 = Vsync, 1 = Vsync from SOG. The power-up
default is 0. These selections are ignored if Register
0x11, Bit 4 = 0.
0x11 4
Vsync
Source
Override
0 = auto Vsync source, 1 = MANUAL Vsync source.
Manual Vsync source is defined in Register 0x11,
Bit 5. The power-up default is 0.
0x11 3
Channel
Select
0 = Channel 0, 1 = Channel 1. The power-up default is
0. These selections are ignored if Register 0x11,
Bit 2 = 0.
0x11
2
Channel Select Override
0 = auto channel select, 1 = manual channel select.
Manual channel select is defined in Register 0x11,
Bit 3. The power-up default is 0.
0x11 1
Interface
Select
0 = analog interface, 1 = digital interface. The power-
up default is 0. These selections are ignored if
Register 0x11, Bit 0 = 0.
0x11
0
Interface Select Override
0 = auto interface select, 1 = manual interface select.
Manual interface select is defined in Register 0x11,
Bit 1. The power-up default is 0.
0x12
7
Input Hsync Polarity
0 = active low, 1 = active high. The power-up default is
1. These selections are ignored if Register 10x2,
Bit 6 = 0.
0x12
6
Hsync Polarity Override
0 = auto Hsync polarity, 1 = manual Hsync polarity.
Manual Hsync polarity is defined in Register 0x11,
Bit 7. The power-up default is 0.
0x12
5
Input Vsync Polarity
0 = active low, 1 = active high. The power-up default is
1. These selections are ignored if Register 0x11,
Bit 4 = 0.
0x12
4
Vsync Polarity Override
0 = auto Vsync polarity, 1 = manual Vsync polarity.
Manual Vsync polarity is defined in Register 0x11,
Bit 5. The power-up default is 0.
COAST AND CLAMP CONTROLS
0x12
3
Input Coast Polarity
0 = active low, 1 = active high. The power-up default
is 1.
0x12
2
Coast Polarity Override
0 = auto Coast polarity, 1 = manual Coast polarity.
The power-up default is 0.
0x12 1
Coast
Source
0 = internal Coast, 1 = external Coast. The power-up
default is 0.
0x12
0
Filter Coast Vsync
0 = use raw Vsync for Coast generation, 1 = use
filtered Vsync for Coast generation The power-up
default is 1.
AD9880
Rev. 0 | Page 40 of 64
0x13 7-0 Precoast
This register allows the internally generated Coast
signal to be applied prior to the Vsync signal. This is
necessary in cases where pre-equalization pulses are
present. The step size for this control is one Hsync
period. For Precoast to work correctly, it is necessary
for the Vsync filter (0x21, Bit 5) and sync processing
filter (0x21 Bit 7) both to be either enabled or
disabled. The power-up default is 0.
0x14 7-0 Postcoast
This register allows the internally generated Coast
signal to be applied following the Vsync signal. This is
necessary in cases where post-equalization pulses are
present. The step size for this control is one Hsync
period. For Postcoast to work correctly, it is necessary
for the Vsync filter (0x21, Bit 5) and sync processing
filter (0x21, Bit 7) both to be either enabled or
disabled. The power-up default is 0.
STATUS OF DETECTED SIGNALS
0x15
7
Hsync0 Detection Bit
Indicates if Hsync0 is active. This bit is used to
indicate when activity is detected on the Hsync0 input
pin. If Hsync is held high or low, activity is not
detected. The sync processing block diagram shows
where this function is implemented. 0 = Hsync0 not
active. 1 = Hsync0 is active.
Table 15. Hsync0 Detection Results
Detect Result
0
No activity detected
1 Activity
detected
0x15
6
Hsync1 Detection Bit
Indicates if Hsync1 is active. This bit is used to indi-
cate when activity is detected on the Hsync1 input pin.
If Hsync is held high or low, activity is not detected.
The sync processing block diagram shows where this
function is implemented. 0 = Hsync1 not active.
1 = Hsync1 is active.
Table 16. Hsync1 Detection Result
Detect Result
0
No activity detected
1 Activity
detected
0x15
5
Vsync0 Detection Bit
Indicates if Vsync0 is active. This bit is used to
indicate when activity is detected on the Vsync0 input
pin. If Vsync is held high or low, activity is not
detected. The sync processing block diagram shows
where this function is implemented. 0 = Vsync0 not
active. 1 = Vsync0 is active.
Table 17. Vsync0 Detection Results
Detect Result
0
No activity detected
1 Activity
detected
0x15
4
Vsync1 Detection Bit
Indicates if Vsync1 is active. This bit is used to
indicate when activity is detected on the Vsync1 input
pin. If Vsync is held high or low, activity is not
detected. The sync processing block diagram shows
where this function is implemented. 0 = Vsync1 not
active. 1 = Vsync1 is active.
Table 18. Vsync1 Detection Results
Detect Result
0
No activity detected
1 Activity
detected
0x15
3
SOG0 Detection Bit
Indicates if SOG0 is active. This bit is used to indicate
when activity is detected on the SOG0 input pin. If
SOG is held high or low, activity is not detected. The
sync processing block diagram shows where this
function is implemented. 0 = SOG0 not active.
1 = SOG0 is active.
Table 19. SOG0 Detection Result
Detect Result
0
No activity detected
1 Activity
detected
0x15
2
SOG1 Detection Bit
Indicates if SOG1 is active. This bit is used to indicate
when activity is detected on the SOG1 input pin. If
SOG is held high or low, activity is not detected. The
sync processing block diagram shows where this
function is implemented. 0 = SOG1 not active.
1 = SOG1 is active.
Table 20. SOG1 Detection Results
Detect Result
0
No activity detected
1 Activity
detected
AD9880
Rev. 0 | Page 41 of 64
0x15
1
Coast Detection Bit
This bit detects activity on the EXTCLK/EXTCOAST
pin. It indicates that one of the two signals is active,
but it doesn't indicate if it is EXTCLK or EXTCOAST.
A dc signal is not detected.
Table 21. Coast Detection Results
Detect Result
0
No activity detected
1 Activity
detected
POLARITY STATUS
0x16 7
Hsync0
Polarity
Indicates the polarity of the Hsync0 input.
Table 22. Detected Hsync0 Polarity Results
Detect Result
0
Hsync polarity negative
1
Hsync polarity positive
0x16
6
Hsync 1 Polarity
Indicates the polarity of the Hsync1 input.
Table 23. Detected Hsync1 Polarity Result
Detect Result
0
Hsync polarity negative
1
Hsync polarity positive
0x16 5
Vsync0
Polarity
Indicates the polarity of the Vsync0 input.
Table 24. Detected Vsync0 Polarity Results
Detect Result
0
Vsync polarity negative
1
Vsync polarity Positive
0x16 4
Vsync1
Polarity
Indicates the polarity of the Vsync1 input.
Table 25. Detected Vsync 1 Polarity Results
Detect Result
0
Vsync polarity negative
1
Vsync polarity positive
0x16 3
Coast
Polarity
Indicates the polarity of the external Coast signal.
Table 26. Detected Coast Polarity Results
Detect Result
0
Coast polarity negative
1
Coast polarity positive
0x16 2
Pseudo
Sync
Detected
0x16
1
Sync Filter Locked
Indicates whether sync filter is locked to periodic sync
signals. 0 = sync filter locked to periodic sync signal.
1 = sync filter not locked.
Table 27. Sync Filter Lock Detect
Detect Result
0
Sync filter locked to periodic sync signal
1
Sync filter not locked to periodic sync signal
0x16
0
Bad Sync Detect
0x17
3-0
Hsyncs per Vsync MSBs
The 4 MSBs of the 12-bit counter that reports the
number of Hsyncs/Vsync on the active input. This is
useful in determining the mode and an aid in setting
the PLL divide ratio.
0x18
7-0
Hsyncs per Vsync LSBs
The 8 LSBs of the 12-bit counter that reports the
number of Hsyncs/Vsync on the active input.
0x19 7-0 Clamp
Placement
Number of pixel clocks after trailing edge of Hsync to
begin clamp. The power-up default is 8.
0x1A 7-0 Clamp
Duration
Number of pixel clocks to clamp. The power-up
default is 0x14.
0x1B
7
Red Clamp Select
This bit selects whether the red channel is clamped to
ground or midscale. Ground clamping is used for red
in RGB applications and midscale clamping is used in
YPrPb (YUV) applications.
Table 28. Red Clamp
Select Result
0
Channel clamped to ground during clamping period
1
Channel clamped to midscale during clamping period
The power-up default is 0.
0x1B 6
Green
Clamp
Select
This bit selects whether the green channel is clamped
to ground or midscale. Ground clamping is normally
used for green in RGB applications and YPrPb (YUV)
applications.
Table 29. Green Clamp
Select Result
0
Channel clamped to ground during clamping period
1
Channel clamped to midscale during clamping period
The power-up default is 0.
AD9880
Rev. 0 | Page 42 of 64
0x1B
5
Blue Clamp Select
This bit selects whether the blue channel is clamped to
ground or midscale. Ground clamping is used for blue
in RGB applications and midscale clamping is used in
YPrPb (YUV) applications.
Table 30. Blue Clamp
Select Result
0
Channel clamped to ground during clamping period
1
Channel clamped to midscale during clamping period
The power-up default is 0.
0x1B
4
Clamp During Coast
This bit permits clamping to be disabled during
Coast. The reason for this is video signals are
generally not at a known backporch or midscale
position during Coast.
Table 31. Clamp During Coast
Select Result
0
Clamping during Coast is disabled
1
Clamping during Coast is enabled
The power-up default is 0.
0x1B 3
Clamp
Disable
Table 32. Clamp Disable
Select Result
0
Internal clamp enabled
1
Internal clamp disabled
The power-up default is 0.
0x1B
2-1
Programmable Bandwidth
Table 33. Bandwidth
Select Result
x0 Low
bandwidth
x1 High
bandwidth
The power-up default is 1.
0x1B
0
Hold Auto Offset
Table 34. Auto Offset Hold
Select Result
0
Normal auto offset operation
1
Hold current offset value
The power-up default is 0.
0x1C
7
Auto Offset Enable
0 = manual offset
1 = auto offset using offset as target code. The power-
up default is 0.
0x1C
6-5
Auto Offset Update Mode
00 = every clamp
01 = every 16 clamps
10 = every 64 clamps
11 = every Vsync
The power-up default setting is 10.
0x1C
4-3
Difference Shift Amount
00 = 100% of difference used to calculate new offset
01 = 50%
10 = 25%
11 = 12.5%
The power-up default is 01.
0x1C
2
Auto Jump Enable
0 = normal operation
1 = if the code >15 codes off, the offset is jumped to
the predicted offset necessary to fix the >15 code mis-
match. The power-up default is 1.
0x1C
1
Post Filter Enable
The post filter reduces the update rate by 1/6 and
requires that all six updates recommend a change
before changing the offset. This prevents unwanted
offset changes.
0 = disable post filer
1 = enable post filter
The power-up default is 1.
0x1C
0
Toggle Filter Enable
The toggle filter looks for the offset to toggle back and
forth and holds it if triggered. This is to prevent
toggling in case of missing codes in the PGA.
1 = toggle filter on, 0 = toggle filter off.
The power-up default is 0.
0x1D 7-0 Slew
Limit
Limits the amount the offset can change by in a single
update. The power-up default is 0x08.
0x1E
7-0
Sync Filter Lock Threshold
This 8-bit register is programmed to set the number
of valid Hsyncs needed to lock the sync filter. This
ensures that a consistent, stable Hsync is present
before attempting to filter. The power-up default
setting is 32d.
0x1F
7-0
Sync Filter Unlock Threshold
This 8-bit register is programmed to set the number of
missing or invalid Hsyncs needed to unlock the sync
filter. This disables the filter operation when there is
no longer a stable Hsync signal. The power-up default
setting is 50d.
AD9880
Rev. 0 | Page 43 of 64
0x20
7-0
Sync Filter Window Width
This 8-bit register sets the distance in 40 MHz clock
periods (25 ns), which is the allowed distance for
Hsync pulses before and after the expected Hsync
edge. This is the heart of the filter in that it only looks
for Hsync pulses at a given time (plus or minus this
window) and then ignores extraneous equalization
pulses that disrupt accurate PLL operation. The
power-up default setting is 10d, or 200 ns on either
side of the expected Hsync.
0x21
7
Sync Processing Filter Enable
This bit selects which Hsync is used for the sync
processing functions of internal Coast, H/V count,
field detection, and Vsync duration counts. A clean
Hsync is fundamental to accurate processing of the
sync. The power-up default setting is 1.
Table 35. Sync Processing Filter Enable
Select Result
0
Sync processing uses raw Hsync or SOG
1
Sync processing uses regenerated Hsync from sync
filter
0x21
6
PLL Sync Filter Enable
This bit selects which signal the PLL uses. It can select
between raw Hsync or SOG, or filtered versions. The
filtering of the Hsync and SOG can eliminate nearly
all extraneous transitions which have traditionally
caused PLL disruption. The power-up default setting
is 0.
Table 36. PLL Sync Filter Enable
Select Result
0
PLL uses raw Hsync or SOG inputs
1
PLL uses filtered Hsync or SOG inputs
0x21
5
Vsync Filter Enable
The purpose of the Vsync filter is to guarantee the
position of the Vsync edge with respect to the Hsync
edge and to generate a field signal. The filter works by
examining the placement of Vsync and regenerating a
correctly placed Vsync one line later. The Vsync is
first checked to see whether it occurs in the Field 0
position or the Field 1 position. This is done by
checking the leading edge position against the sync
separator threshold and the Hsync position. The
Hsync width is divided into four quadrants with
Quadrant 1 starting at the Hsync leading edge plus a
sync separator threshold. If the Vsync leading edge
occurs in Quadrant 1 or 4 then the field is set to 0 and
the output Vsync is placed coincident with the Hsync
leading edge. If the Vsync leading edge occurs in
Quadrant 2 or 3 then the field is set to 1 and the
output Vsync leading edge is placed in the center of
the line. In this way, the Vsync filter creates a
predictable relative position between Hsync and
Vsync edges at the output.
If the Vsync occurs near the Hsync edge, this guaran-
tees that the Vsync edge follows the Hsync edge. This
performs filtering also in that it requires a minimum
of 64 lines between Vsyncs. The Vsync filter cleans up
extraneous pulses that might occur on the Vsync. This
should be enabled whenever the Hsync/Vsync count is
used. Setting this bit to 0 disables the Vsync filter.
Setting this bit to 1 enables the Vsync filter. Power-up
default is 0.
Table 37. Vsync Filter Enable
Vsync Filter Bit
Result
0
Vsync filter disabled
1
Vsync filter enabled
0x21 4
Vsync
Duration
Enable
This enables the Vsync duration block which is
designed to be used with the Vsync filter. Setting the
bit to 0 leaves the Vsync output duration unchanged;
setting the bit to 1 sets the Vsync output duration
based on Register 0x22. The power-up default is 0.
Table 38. Vsync Duration Enable
Vsync
Duration Bit
Result
0
Vsync output duration unchanged
1
Vsync output duration set by 0x22
0x21
3
Auto Offset Clamp Mode
This bit specifies if the auto offset measurement takes
place during clamp or either 10 or 16 clocks afterward.
The measurement takes 6 clock cycles.
Table 39. AO Clamp Mode
AO
Offset Mode
Result
0
Auto offset measurement takes place during
clamp period
1
Auto offset measurement is set by 0x21, Bit 2
0x21
2
Auto Offset Clamp Length
This bit sets the delay following the end of the clamp
period for AO measurement. This bit is valid only if
Register 0x21, Bit 3 = 1.
Table 40. AO Clamp Length
AO Offset
Clamp Bit
Result
0
Delay is 10 clock cycles
1
Delay is 16 clock cycles
0x22 7-0 Vsync
Duration
This is used to set the output duration of the Vsync,
and is designed to be used with the Vsync filter. This
is valid only if Register 0x21, Bit 4 is set to 1. Power-up
default is 4.
AD9880
Rev. 0 | Page 44 of 64
0x23 7-0 Hsync
Duration
An 8 bit register that sets the duration of the Hsync
output pulse. The leading edge of the Hsync output is
triggered by the internally generated, phase-adjusted
PLL feedback clock. The AD9880 then counts a
number of pixel clocks equal to the value in this
register. This triggers the trailing edge of the Hsync
output, which is also phase-adjusted. The power-up
default is 32.
0x24 7
Hsync
Output
Polarity
This bit sets the polarity of the Hsync output. Setting
this bit to 0 sets the Hsync output to active low. Setting
this bit to 1 sets the Hsync output to active high.
Power-up default setting is 1.
Table 41. Hsync Output Polarity Settings
Hsync Output Polarity Bit
Result
0
Hsync output polarity negative
1
Hsync output polarity positive
0x24
6
Vsync Output Polarity
This bit sets the polarity of the Vsync output (both
DVI and analog). Setting this bit to 0 sets the Vsync
output to active low. Setting this bit to 1 sets the Vsync
output to active high. Power-up default is 1.
Table 42. Vsync Output Polarity Settings
Vsync Output Polarity Bit
Result
0
Vsync output polarity is negative
1
Vsync output polarity is positive
0x24
5
Display Enable Output Polarity
This bit sets the polarity of the display enable (DE) for
both DVI and analog.
Table 43. DE Output Polarity Settings
DE Output Polarity Bit
Result
0
DE output polarity is negative
1
DE output polarity is positive
The power-up default is 1.
0x24 4
Field
Output
Polarity
This bit sets the polarity of the field output signal on
Pin 21. The power-up default setting is 1.
Table 44. Field Output Polarity
Select Result
0
Active low = even field; active high = odd field
1
Active low = odd field; active high = even field
Output field polarity (both DVI and analog)
0 = active low out
1 = active high out
The power-up default is 1.
0x24
3
SOG Output Polarity
This bit sets the polarity of the SOGOUT signal
(analog only).
Table 45. SOGOUT Polarity Settings
SOGOUT Result
0 Active
low
1 Active
high
The power-up default setting is 1.
0x24
2-1
SOG Output Select
These register bits control the output on the SOGOUT
pin. Options are the raw SOG from the slicer (this is
the unprocessed SOG signal produced from the sync
slicer), the raw Hsync, the regenerated sync from the
sync filter, which can generate missing syncs because
of coasting or drop-out, or the filtered sync that
excludes extraneous syncs not occurring within the
sync filter window.
Table 46. SOGOUT Polarity Settings
SOGOUT Select
Function
00
Raw SOG from sync slicer (SOG0 or SOG1)
01
Raw Hsync (Hsync0 or Hsync1)
10
Regenerated sync from sync filter
11
Hsync to PLL
The power-up default setting is 11.
0x24 0
Output
Clock
Invert
This bit allows inversion of the output clock as
specified by Register 0x25, Bits 7 to 6. The power-up
default setting is 0.
Table 47. Output Clock Invert
Select Result
0 Noninverted
clock
1 Inverted
clock
0x25 7-6 Output
Clock
Select
These bits select the clock output on the DATACLK
pin. They include 1/2 clock, a 2 clock, a 90 phase
shifted clock or the normal pixel clock. The power-up
default setting is 01.
AD9880
Rev. 0 | Page 45 of 64
Table 48. Output Clock Select
Select Result
00
pixel clock
01
1 pixel clock
10
2 pixel clock
11
90 phase 1 pixel clock
0x25 5-4 Output
Drive
Strength
These two bits select the drive strength for all the
high-speed digital outputs (except VSOUT, A0 and
O/E field). Higher drive strength results in faster
rise/fall times and in general makes it easier to capture
data. Lower drive strength results in slower rise/fall
times and helps to reduce EMI and digitally generated power
supply noise. The power-up default setting is 11.
Table 49. Output Drive Strength
Output Drive
Result
00
Low output drive strength
01
Medium low output drive strength
10
Medium high output drive strength
11
High output drive strength
0x25 3-2 Output
Mode
These bits choose between four options for the output
mode, one of which is exclusive to an HDMI input.
4:4:4 mode is standard RGB; 4:2:2 mode is YCrCb,
which reduces the number of active output pins from
24 to 16; 4:4:4 double data rate (DDR) output mode;
and the data is RGB mode, but changes on every clock
edge. The power-up default setting is 00.
Table 50. Output Mode
Output
Mode Result
00
4:4:4 RGB mode
01
4:2:2 YCrCb mode + DDR 4:2:2 on blue (secondary)
10
DDR 4:4:4: DDR mode + DDR 4:2:2 on blue
(secondary)
11
12-bit 4:2:2 (HDMI option only)
The power-up default is 00.
0x25 1
Primary
Output
Enable
This bit places the primary output in active or high
impedance mode.
The primary output is designated when using either
4:2:2 or DDR 4:4:4. In these modes, the data on the
red and green output channels is the primary output,
while the output data on the blue channel (DDR
YCrCb) is the secondary output. The power-up
default setting is 1.
Table 51. Primary Output Enable
Select Result
0
Primary output is in high impedance mode
1
Primary output is enabled
0x25 0
Secondary
Output
Enable
This bit places the secondary output in active or high
impedance mode.
The secondary output is designated when using either
4:2:2 or DDR 4:4:4. In these modes the data on the
blue output channel is the secondary output while the
output data on the red and green channels is the
primary output. Secondary output is always a DDR
YCrCb data mode. The power-up default setting is 0.
Table 52. Secondary Output Enable
Select Result
0
Secondary output is in high impedance mode
1
Secondary output is enabled
0x26 7
Output
Three-State
When enabled, this bit puts all outputs (except
SOGOUT) in a high impedance state. The power-up
default setting is 0.
Table 53. Output Three-State
Select Result
0 Normal
outputs
1
All outputs (except SOGOUT) in high impedance mode
0x26 6
SOG
Three-State
When enabled, this bit allows the SOGOUT pin to be
placed in a high impedance state. The power-up
default setting is 0.
Table 54. SOGout Three-State
Select Result
0
Normal SOG output
1
SOGOUT pin is in high impedance mode
0x26 5
SPDIF
Three-State
When enabled, this bit places the SPDIF audio output
pins in a high impedance state. The power-up default
setting is 0.
Table 55. SOGOUT Three-State
Select Result
0
Normal SPDIF output
1
SPDIF pins in high impedance mode
0x26 4
I2S
Three-State
When enabled, this bit places the I2S output pins in a
high impedance state. The power-up default setting
is 0.
AD9880
Rev. 0 | Page 46 of 64
Table 56. SOGOUT Three-State
Select Result
0
Normal I2S output
1
I2S pins in high impedance mode.
0x26 3
Power-Down
Polarity
This bit defines the polarity of the input power-down
pin. The power-up default setting is 1.
Table 57. Power-Down Input Polarity
Select Result
0
Power-down pin is active low
1
Power-down pin is active high
0x26 2-1 Power-Down
Pin
Function
These bits define the different operational modes of
the power-down pin. These bits are functional only
when the power-down pin is active; when it is not
active, the part is powered up and functioning. The
power-up default setting is 00.
Table 58. Power Down Pin Function
PWRDN
Pin
Function
Result
00
The chip is powered down and all outputs except
SOGOUT are in high impedance mode.
01
The chip is powered down and all outputs are in
high impedance mode.
10
The chip remains powered up, but all outputs
except SOGOUT are in high impedance mode.
11
The chip remains powered up, but all outputs are
in high impedance mode.
0x26 0
Power-Down
This bit is used to put the chip in power-down mode.
In this mode the chips power dissipation is reduced to
a fraction of the typical power (see Table 1 for exact
power dissipation). When in power-down, the
HSOUT, VSOUT, DATACK, and all 30 of the data
outputs are put into a high impedance state. Note that
the SOGOUT output is not put into high impedance.
Circuit blocks that continue to be active during
power-down include the voltage references, sync
processing, sync detection, and the serial register.
These blocks facilitate a fast start-up from power-
down. The power-up default setting is 0.
Table 59. Power-Down Settings
Select Result
0 Normal
operation
1 Power-Down
0x27
7
Auto Power-Down Enable
This bit enables the chip to go into low power mode,
or seek mode if no sync inputs are detected. The
power-up default setting is 1.
Table 60. Auto Power-Down Select
Auto
Power Down
Result
0
Auto power down disabled
1
Chip powers down if no sync inputs present
0x27
6
HDCP A0 Address
This bit sets the LSB of the address of the HDCP I
2
C.
This should be set to 1 only for a second receiver in a
dual-link configuration. The power-up default is 0.
0x27
5
MCLK External Enable
This bit enables the MCLK to be supplied externally. If
an external MCLK is used, then it must be locked to
the video clock according to the CTS and N available
in the I
2
C. Any mismatch between the internal MCLK
and the input MCLK results in dropped or repeated
audio samples. The power-up default setting is 0.
Table 61. MCLK External Select
Select Result
0
Use internally generated MCLK
1
Use external MCLK input
BT656 GENERATION
0x27 4
BT656
Enable
This bit enables the output to be BT656-compatible
with defined start of active video (SAV) and end of
active video (EAV) controls to be inserted. These
require specification of the number of active lines,
active pixels per line, and delays to place these
markers. The power-up default setting is 0.
Table 62. BT656 Mode
Select Result
0
Disable BT656 video mode
1
Enable BT656 video mode
0x27 3
Force
DE
Generation
This bit allows the use of the internal DE generator in
DVI mode. The power-up default setting is 0.
Table 63. DE Generation
Select Result
0
Internal DE generation disabled
1
Force DE generation via programmed registers
0x27 2-0 Interlace
Offset
These bits define the offset in Hsyncs from Field 0 to
Field 1. The power-up default setting is 000.
0x28 7-2 Vsync
Delay
These bits set the delay (in lines) from the leading
edge of Vsync to active video. The power-up default
setting is 24.
AD9880
Rev. 0 | Page 47 of 64
0x28 1-0 Hsync
Delay
MSBs
Along with the eight bits following these ten bits set
the delay (in pixels) from the Hsync leading edge to
the start of active video. The power-up default setting
is 0x104.
0x29
7-0
Hsync Delay LSBs
See the Hsync Delay MSBs section.
0x2A
3-0
Line Width MSBs
Along with the 8 bits following these 12 bits, set the
width of the active video line (in pixels). The power-
up default setting is 0x500.
0x2B
7-0
Line Width LSBs
See the line width MSBs section.
0x2C
3-0
Screen Height MSBs
Along with the 8 bits following these 12 bits, set the
height of the active screen (in lines). The power-up
default setting is 0x2D0.
0x2D
7-0
Screen Height LSBs
See the Screen Height MSBs section.
0x2E 7
Ctrl
Enable
When set, this bit allows Ctrl [3:0] signals decoded
from the DVI to be output on the I2S data pins. The
power-up default setting is 0.
Table 64. CTRL Enable.
Select Result
0
I2S signals on I2S lines
1
Ctrl [3:0] output on I2S lines
0x2E
6-5
I2S Output Mode
These bits select between four options for the I2S
output: I2S, right-justified, left-justified, or raw
IEC60958 mode. The power-up default setting is 00.
Table 65. I2S Output Select
I2S Output Mode
Result
00 I2S
mode
01 Right-Justified
10 Left-Justified
11 Raw
IEC60958
mode
0x2E
4-0
I2S Bit Width
These bits set the I2S bit width for right-justified
mode. The power-up default setting is 24 bits.
0x2F 6
TMDS
Sync
Detect
This read-only bit indicates the presence of a TMDS
DE.
Table 66. Detected TMDS Sync Results
Detect Result
0
No TMDS DE present
1
TMDS DE detected
0x2F 5
TMDS
Active
This read only bit indicates the presence of a TMDS
clock.
Table 67. Detected TMDS Clock Results
Detect Result
0
No TMDS clock present
1
TMDS clock detected
0x2F 4
AV
Mute
This read-only bit indicates the presence of AV (audio
video) mute based on general control packets.
Table 68. Detected AV Mute Status
Detect Result
0
AV not muted
AV
muted
0x2F
3
HDCP Keys Read
This read-only bit reports if the HDCP keys were read
successfully.
Table 69. HDCP Keys
Detect Result
0
Failure to read HDCP keys
1
HDCP keys read
0x2F 2-0 HDMI
Quality
These read-only bits indicate a level of HDMI quality
based on the DE (display enable) edges. A larger
number indicates a higher quality.
0x30
6
HDMI Content Encrypted
This read-only bit is high when HDCP decryption is
in use (content is protected). The signal goes low
when HDCP is not being used. Customers can use this
bit to determine whether or not to allow copying of
the content. The bit should be sampled at regular
intervals since it can change on a frame by frame
basis.
Table 70. HDCP Activity
Detect Result
0
HDCP not in use
1
HDCP decryption in use
0x30
5
DVI Hsync Polarity
This read-only bit indicates the polarity of the DVI
Hsync.
AD9880
Rev. 0 | Page 48 of 64
Table 71. DVI Hsync Polarity Detect
Detect Result
0
DVI Hsync polarity is low active
1
DVI Hsync polarity is high active
0x30 4
DVI
Vsync
Polarity
This read-only bit indicates the polarity of the DVI
Vsync.
Table 72. DVI Vsync Polarity Detect
Detect Result
0
DVI Vsync polarity is low active
1
DVI Vsync polarity is high active
0x30
3-0
HDMI Pixel Repetition
These read-only bits indicate the pixel repetition on
DVI. 0 = 1, 1 = 2, 2 = 3, up to a maximum
repetition of 10 (0x9).
Table 73.
Select Repetition
Multiplier
0000 1
0001 2
0010 3
0011 4
0100 5
0101 6
0110 7
0111 8
1000 9
1001 10
MACROVISION
0x31
7-4
Macrovision Pulse Max
These bits set the pseudo sync pulse width maximum
for Macrovision detection in pixel clocks. This is
functional for 13.5 MHz SDTV or 27 MHz progressive
scan. Power up default is 9.
0x31
3-0
Macrovision Pulse Min
These bits set the pseudo sync pulse width maximum
for Macrovision detection in pixel clocks. This is
functional for 13.5 MHz SDTV or 27 MHz progressive
scan. Power up default is 6.
0x32 7
Macrovision
Oversample
Enable
Tells the Macrovision detection engine whether we are
oversampling or not. This accommodates 27 MHz
sampling for SDTV and 54 MHz sampling for
progressive scan and is used as a correction factor for
clock counts. Power up default is 0.
0x32
6
Macrovision PAL Enable
Tells the Macrovision detection engine to enter PAL
mode when set to 1. Default is 0 for NTSC mode.
0x32
5-0
Macrovision Line Count Start
Sets the start line for Macrovision detection. Along
with Register 0x33, Bits [5:0] they define the region
where MV pulses are expected to occur. The power-up
default is Line 13.
0x33
7
Macrovision Detect Mode
0 = standard definition
1 = progressive scan mode
0x33
6
Macrovision Settings Override
This defines whether preset values are used for the
MV line counts and pulse widths or the values stored
in I
2
C registers.
0 = use hard coded settings for line counts and pulse
widths
1 = use I
2
C values for these settings
0x33
5-0
Macrovision Line Count End
Sets the end line for Macrovision detection. Along
with Register 0x32, Bits [5:0] they define the region
where MV pulses are expected to occur. The power up
default is Line 21.
0x34
7-6
Macrovision Pulse Limit Select
Sets the number of pulses required in the last three
lines (SD mode only). If there is not at least this
number of MV pulses, the engine stops. These two
bits define the following pulse counts:
00 = 6
01 = 4
10 = 5 (default)
11 = 7
0x34
5
Low Frequency Mode
Sets whether the audio PLL is in low frequency mode
or not. Low frequency mode should only be set for
pixel clocks < 80 MHz.
0x34
4
Low Frequency Override
Allows the previous bit to be used to set low frequency
mode rather than the internal autodetect.
0x34
3
Up Conversion Mode
0 = repeat Cb/Cr values
1 = interpolate Cb/Cr values
0x34
2
CbCr Filter Enable
Enables the FIR filter for 4:2:2 CbCr output.
AD9880
Rev. 0 | Page 49 of 64
COLOR SPACE CONVERSION
The default power up values for the color space con-
verter coefficients (R0x35 through R0x4C) are set for
ATSC RGB to YCbCr conversion. They are completely
programmable for other conversions.
0x34
1
Color space Converter Enable
This bit enables the color space converter. The power-
up default setting is 0.
Table 74. Color space Converter
Select Result
0
Disable color space converter
1
Enable color space converter
0x35
6-5 Color space Converter Mode
These two bits set the fixed point position of the CSC
coefficients, including the A4, B4, and C4 offsets.
Table 75. CSC Fixed Point Converter Mode
Select Result
00
1.0, -4096 to 4095
01
2.0, -8192 to 8190
1
4.0, -16384 to 16380
0x35
4-0
Color space Conversion Coefficient A1 MSBs
These 5 bits form the 5 MSBs of the Color space
Conversion Coefficient A1. This combined with the
8 LSBs of the following register form a 13-bit twos
complement coefficient which is user programmable.
The equation takes the form of:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
The default value for the 13 bit A1 coefficient is
0x0C52.
0x36
7-0
Color space Conversion Coefficient A1 LSBs
See the Register 0x35 section.
0x37
4-0
CSC A2 MSBs
These five bits form the 5 MSBs of the Color space
Conversion Coefficient A2. Combined with the 8
LSBs of the following register they form a 13 bit twos
complement coefficient that is user programmable.
The equation takes the form of:
R
OUT
= (A1 R
IN
) + (A2 G
IN
) + (A3 B
IN
) + A4
G
OUT
= (B1 R
IN
) + (B2 G
IN
) + (B3 B
IN
) + B4
B
OUT
= (C1 R
IN
) + (C2 G
IN
) + (C3 B
IN
) + C4
The default value for the 13-bit A2 coefficient is
0x0800.
0x38
7-0
CSC A2 LSBs
See the Register 0x37 section.
0x39
4-0
CSC A3 MSBs
The default value for the 13-bit A3 is 0x0000.
0x3A
7-0
CSC A3 LSBs
0x3B
4-0
CSC A4 MSBs
The default value for the 13-bit A4 is 0x19D7.
0x3C
7-0
CSC A4 LSBs
0x3D
4-0
CSC B1 MSBs
The default value for the 13-bit B1 is 0x1C54.
0x3E
7-0
CSC B1 LSBs
0x3F
4-0
CSC B2 MSB
The default value for the 13-bit B2 is 0x0800.
0x40
7-0
CSC B2 LSBs
0x41
4-0
CSC B3 MSBs
The default value for the 13-bit B3 is 0x1E89.
0x42
7-0
CSC B3 LSBs
0x43
4-0
CSC B4 MSBs
The default value for the 13-bit B4 is 0x0291.
0x44
7-0
CSC B4 LSBs
0x45
4-0
CSC C1 MSBs
The default value for the 13-bit C1 is 0x0000.
0x46
7-0
CSC C1 LSBs
0x47
4-0
CSC C2 MSBs
The default value for the 13 bit C2 is 0x0800.
0x48
7-0
CSC C2 LSBs
0x49
4-0
CSC C3 MSBs
The default value for the 13-bit C3 is 0x0E87.
0x4A
7-0
CSC C3 LSBs
0x4B
4-0
CSC C4 MSBs
The default value for the 13-bit C4 is 0x18BD.
0x4C
7-0
CSC C4 LSBs
0x57
7
A/V Mute Override
0x57
6
A/V Mute Value
0x57
3
Disable AV Mute
0x57
2
Disable Audio Mute
0x58
7
MCLK PLL Enable
This bit enables the use of the analog PLL.
0x58 6-4 MCLK
PLL_N
These bits control the division of the MCLK out of the
PLL.
AD9880
Rev. 0 | Page 50 of 64
Table 76.
PLL_N [2:0]
MCLK Divide Value
0 /1
1 /2
2 /3
3 /4
4 /5
5 /6
6 /7
7 /8
0x58 3
N_CTS_Disable
This bit makes it possible to prevent the N/CTS packet
on the link from writing to the N and CTS registers.
0x58 2-0 MCLK
fs_N
These bits control the multiple of 128 fs used for
MCLK out.
Table 77.
MCLK fs_N [2:0]
fs Multiple
0 128
1 256
2 384
3 512
4 640
5 768
6 896
7 1024
0x59 6
MDA/MCL
PU
Disable
This bit disables the inter MDA/MCL pull-ups.
0x59
5
CLK Term O/R
This bit allows for overriding during power down.
0 = auto, 1 = manual.
0x59
4
Manual CLK Term
This bit allows normal clock termination or
disconnects this. 0 = normal, 1 = disconnected.
0x59
2
FIFO Reset UF
This bit resets the audio FIFO if underflow is detected.
0x59
1
FIFO Reset OF
This bit resets the audio FIFO if overflow is detected.
0x59 0
MDA/MCL
Three-State
This bit three-states the MDA/MCL lines to allow in-
circuit programming of the EEPROM.
0x5A 6-0 Packet
Detect
This register indicates if a data packet in specific
sections has been detected. These seven bits are
updated if any specific packet has been received since
last reset or loss of clock detect. Normal is 0x00.
Table 78.
Packet Detect Bit
Packet Detected
0 AVI
infoframe
1 Audio
infoframe
2 SPD
infoframe
3
MPEG Source infoframe
4 ACP
packets
5 ISRC1
packets
6 ISRC2
packets
0x5B 3
HDMI
Mode
0 = DVI, 1 = HDMI.
0x5E
7-6
Channel Status Mode
0x5E
5-3
PCM Audio Data
0x5E 2
Copyright
Information
0x5E
1
Linear PCM Identification
0x5E
0
Use of Channel Status Block
0x5F
7-0
Channel Status Category Code
0x60 7-4 Channel
Number
0x60 3-0 Source
Number
0x61 5-4 Clock
Accuracy
0x61 3-0 Sampling Frequency
Table 79.
Code Frequency
(kHz)
0x0 44.1
0x2 48
0x3 32
0x8 88.2
0xA 96
0xC 176.4
0xE 192
0x62 3-0 Word
Length
0x7B
7-0
CTS (Cycle Time Stamp) (19-12)
These are the most significant 8 bits of a 20-bit word
used in the 20-bit N term in the regeneration of the
audio clock.
0x7C 7-0 CTS
(11-4)
0x7D 7-4 CTS
(3-0)
0x7D 3-0 N
(19-16)
These are the most significant 4 bits of a 20-bit word
used along with the 20-bit CTS term to regenerate the
audio clock.
0x80
AVI Infoframe Version
0x81 6-5 Y
[1:0]
This register indicates whether data is RGB, 4:4:4 or
4:2:2.
AD9880
Rev. 0 | Page 51 of 64
Table 80.
Y Video
Data
00 RGB
01 YCbCr
4:2:2
10 YCbCr
4:4:4
0x81
4
Active Format Information Present
0 = no data
1 = active format information valid
0x81 3-2 Bar
Information
Table 81.
B Bar
Type
00
No bar information
01
Horizontal bar information valid
10
Vertical bar information valid
11
Horizontal and vertical bar information valid
0x81 1-0 Scan
Information
Table 82.
S [1:0]
Scan Type
00 No
information
01 Overscanned
(television)
10 Underscanned
(computer)
0x82 7-6 Colorimetry
Table 83.
C [1:0]
Colorimetry
00 No
data
01
SMPTE 170M, ITU601
10 ITU
709
0x82
5-4
Picture Aspect Ratio
Table 84.
M[1:0] Aspect
Ratio
00 No
data
01 4:3
10 16:9
0x82
3-0
Active Format Aspect Ratio
Table 85.
R [3:0]
Active Format A/R
0x8
Same as picture aspect ratio (M [1:0])
0x9 4:3
(center)
0xA 16:9
(center)
0xB 14:9
(center)
0x83
1-0
Nonuniform Picture Scaling
Table 86.
SC [1:0]
Picture Scaling
00
No known nonuniform scaling
01
Has been scaled horizontally
10
Has been scaled vertically
11
Has been scaled both horizontally and vertically
0x84 6-0 Video
ID
Code
See CEA EDID short video descriptors.
0x85 3-0 Pixel
Repeat
This value indicates how many times the pixel was
repeated. 0x0 = no repeats, sent once, 0x8 = 8 repeats,
sent 9 times, and so on.
0x86
7-0
Active Line Start LSB
Combined with the MSB in Register 0x88, these bits
indicate the beginning line of active video. All lines
before this comprise a top horizontal bar. This is used
in letter box modes. If the 2-byte value is 0x00, there is
no horizontal bar.
0x87
6-0
New Data Flags (NDF)
This register indicates whether data in specific
sections has changed. In the address space from 0x80
to 0xFF, each register address ending in 0b111 (for
example, 0x87, 0x8F, 0x97, 0xAF) is an NDF register.
They all have the same data and all are reset upon
reading any one of them.
Table 87.
NDF Bit number
Changes Occurred
0 AVI
infoframe
1 Audio
infoframe
2 SPD
infoframe
3
MPEG Source infoframe
4 ACP
packets
5 ISRC1
packets
6 ISRC2
packets
0x88
7-0
Active Line Start MSB
See Register 0x86.
0x89
7-0
Active Line End LSB
Combined with the MSB in Register 0x8A these bits
indicate the last line of active video. All lines past this
comprise a lower horizontal bar. This is used in letter-
box modes. If the 2-byte value is greater than the
number of lines in the display, there is no lower
horizontal bar.
0x8A
7-0
Active Line End MSB
See Register 0x89.
0x8B
7-0
Active Pixel Start LSB
Combined with the MSB in Register 0x8C, these bits
indicate the first pixel in the display which is active
video. All pixels before this comprise a left vertical bar.
If the 2-byte value is 0x00, there is no left bar.
0x8C
7-0
Active Pixel Start MSB
See Register 0x8B.
AD9880
Rev. 0 | Page 52 of 64
0x8D
7-0
Active Pixel End LSB
Combined with the MSB in Register 0x8E these bits
indicate the last active video pixel in the display. All
pixels past this comprise a right vertical bar. If the
2-byte value is greater than the number of pixels in the
display, there is no vertical bar.
0x8E
7-0
Active Pixel End MSB
See Register 0x8D.
0x8F 6-0 NDF
See Register 0x87.
0x90
7-0
Audio Infoframe Version
0x91 7-4 Audio
Coding
Type
These bits identify the audio coding so that the
receiver may process audio properly.
Table 88.
CT [3:0]
Audio Coding
0x0
Refer to stream header
0x1 IEC60958
PCM
0x2 AC-3
0x3
MPEG1 (Layers 1 and 2)
0x4
MP3 (MPEG1 Layer 3)
0x5 MPEG2
(multichannel)
0x6 AAC
0x7 DTS
0x8 ATRAC
0x91
2-0
Audio Channel Count
These bits specify how many audio channels are being
sent--2 channels to 8 channels.
Table 89.
CC [2:0]
Channel Count
000
Refer to stream header
001 2
010 3
011 4
100 5
101 6
110 7
111 8
0x92 4-2 Sampling Frequency
0x92 1-0 Ample
Size
0x93
7-0
Max Bit Rate
For compressed audio only when this value is
multiplied by 8 kHz represents the maximum bit rate.
A value of 0x08 in this field would yield a maximum
bit rate of (8 kHz 8 kHz = 64 kHz).
0x94 7-0 Speaker
Mapping
These bits define the mapping (suggested placement)
of speakers.
Table 90.
Abbreviation Speaker
Placement
FL Front
left
FC Front
center
FR Front
right
FCL
Front center left
FCR
Front center right
RL Rear
left
RC Rear
center
RR Rear
right
RCL
Rear center left
RCR
Rear center right
LFE
Low frequency effect
AD9880
Rev. 0 | Page 53 of 64
Table 91.
CA Channel
Number
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
0 0 0 0 0
FR
FL
0 0 0 0 1
LFE FR
FL
0 0 0 1 0
FC
FR FL
0 0 0 1 1
FC LFE FR FL
0 0 1 0 0
RC
FR FL
0 0 1 0 1
RC LFE FR FL
0 0 1 1 0
RC FC
FR FL
0 0 1 1 1
RC FC LFE FR FL
0 1 0 0 0
RR RL
FR FL
0 1 0 0 1
RR RL LFE FR FL
0 1 0 1 0
RR RL FC
FR FL
0 1 0 1 1
RR RL FC LFE
FR FL
0 1 1 0 0
RC
RR RL
FR FL
0 1 1 0 1
RC
RR RL
LFE
FR FL
0 1 1 1 0
RC
RR RL FC
FR FL
0 1 1 1 1
RC
RR RL FC LFE
FR FL
1 0 0 0 0 RRC
RLC
RR RL
FR FL
1 0 0 0 1 RRC
RLC
RR RL
LFE
FR FL
1 0 0 1 0 RRC
RLC
RR RL FC
FR FL
1 0 0 1 1 RRC
RLC
RR RL FC LFE
FR FL
1 0 1 0 0 FRC
FLC
v
FR FL
1 0 1 0 1 FRC
FLC
v
LFE
FR FL
1 0 1 1 0 FRC
FLC
FC
FR FL
1 0 1 1 1 FRC
FLC
FC LFE
FR FL
1 1 0 0 0 FRC
FLC
RC
FR FL
1 1 0 0 1 FRC
FLC
RC
LFE
FR FL
1 1 0 1 0 FRC
FLC
RC FC
FR FL
1 1 0 1 1 FRC
FLC
RC FC LFE
FR FL
1 1 1 0 0 FRC
FLC
RR RL
v
FR FL
1 1 1 0 1 FRC
FLC
RR RL
LFE
FR FL
1 1 1 1 0 FRC
FLC
RR RL FC
FR FL
1 1 1 1 1 FRC
FLC
RR RL FC LFE
FR FL
0x95 7
Down-Mix
Inhibit
0x95
6-3
Level Shift Values
These bits define the amount of attenuation. The value
directly corresponds to the amount of attenuation: for
example, 0000 = 0 dB, 0001 = 1 dB to 1111 = 15 dB
attenuation.
0x96 7-0 Reserved
0x97
6-0
New Data Flags
See Register 0x87 for a description.
0x98 7-0 Source
Product Description (SPD)
Infoframe Version
0x99
7-0
Vender Name Character 1 (VN1)
This is the first character in eight that is the name of
the company that appears on the product. The data
characters are 7-bit ASCII code.
0x9A 7-0 VN2
0x9B 7-0 VN3
0x9C 7-0 VN4
0x9D 7-0 VN5
0x9E 7-0 VN6
0x9F
6-0
New Data Flags
See Register 0x87 for a description.
AD9880
Rev. 0 | Page 54 of 64
0xA0 7-0 VN7
0xA1 7-0 VN8
0xA2
7-0
Product Description Character 1 (PD1)
This is the first character of 16 which contains the
model number and a short description of the product.
The data characters are 7-bit ASCII code.
0xA3 7-0 PD2
0xA4 7-0 PD3
0xA5 7-0 PD4
0xA6 7-0 PD5
0xA7
6-0
New Data Flags
See Register 0x87 for a description.
0xA8 7-0 PD6
0xA9 7-0 PD7
0xAA 7-0 PD8
0xAB 7-0 PD9
0xAC 7-0 PD10
0xAD 7-0
PD11
0xAE 7-0 PD12
0xAF
6-0
New Data Flags
See Register 0x87 for a description.
0xB0 7-0 PD13
0xB1 7-0 PD14
0xB2 7-0 PD15
0xB3 7-0 PD16
0xB4
7-0
Source Device Information Code
These bytes classify the source device.
Table 92.
SDI Code
Source
0x00 Unknown
0x01 Digital
STB
0x02 DVD
0x03 D-VHS
0x04 HDD
video
0x05 DVC
0x06 DSC
0x07 Video
CD
0x08 Game
0x09 PC
general
0xB7
6-0
New Data Flags
See Register 0x87 for a description.
0xB8
7-0
MPEG Source Infoframe Version
0xB9
7-0
MPEG Bit Rate Byte 0 (MB0)
This is the lower 8 bits of 32 bits that specify the
MPEG bit rate in Hz.
0xBA 7-0 MB1
0xBB 7-0 MB2
0xBC 7-0 MB3--Upper
Byte
0xBD 4
Field
Repeat
This defines whether the field is new or repeated.
Table 93.
FR Field
Type
0
New field or picture
1 Repeated
field
0xBD 1-0 MPEG
Frame
This identifies the frame as I, B, or P.
Table 94.
MF [1-0]
Frame Type
00 Unknown
01 I--picture
10 B--picture
11 P--picture
0xBE 7-0 Reserved
0xBF
6-0
New Data Flags
See Register 0x87 for a description.
0xC0
7-0
Audio Content Protection Packet (ACP
Type)
These bits define which audio content protection is used.
Table 95.
Code ACP
Type
0x00 Generic
audio
0x01
IEC 60958-identified audio
0x02 DVD-audio
0x03
Reserved for super audio CD (SACD)
0x04--0xFF Reserved
0xC1
ACP Packet Byte 0 (ACP_PB0)
0xC2 7-0 ACP_PB1
0xC3 7-0 ACP_PB2
0xC4 7-0 ACP_PB3
0xC5 7-0 ACP_PB4
0xC7
6-0
New Data Flags
See Register 0x87 for a description.
0xC8
7
International Standard Recording Code
(ISRC1) Continued
This bit indicates that a continuation of the 16 ISRC1
packet bytes (an ISRC2 packet) is being transmitted.
0xC8 6
ISRC1
Valid
This bit is an indication of the whether ISRC1 packet
bytes are valid.
AD9880
Rev. 0 | Page 55 of 64
Table 96.
ISRC1 Valid
Description
0
ISRC1 status bits and PBs not valid
1
ISRC1 status bits and PBs valid
0xC8 2-0 ISRC
Status
These bits define where in the ISRC track the samples
are: at least two transmissions of 001 occur at the
beginning of the track, while in the middle of the
track, continuous transmission of 010 occurs followed
by at least two transmissions of 100 near the end of the
track.
0xC9
7-0
ISRC1 Packet Byte 0 (ISRC1_PB0)
0xCA 7-0 ISRC1_PB1
0xCB 7-0 ISRC1_PB2
0xCC 7-0 ISRC1_PB3
0xCD 7-0 ISRC1_PB4
0xCE 7-0 ISRC1_PB5
0xCF
6-0
New Data Flags
See Register 0x87 for a description.
0xD0 7-0 ISRC1_PB6
0xD1 7-0 ISRC1_PB7
0xD2 7-0 ISRC1_PB8
0xD3 7-0 ISRC1_PB9
0xD4 7-0 ISRC1_PB10
0xD5 7-0 ISRC1_PB11
0xD6 7-0 ISRC1_PB12
0xD7
6-0
New Data Flags
See Register 0x87 for a description.
0xD8 7-0 ISRC1_PB13
0xD9 7-0 ISRC1_PB14
0xDA 7-0
ISRC1_PB15
0xDB 7-0 ISRC1_PB16
0xDC
7-0
ISRC2 Packet Byte 0 (ISRC2_PB0)
This is transmitted only when the ISRC continue bit
(Register 0xC8 Bit 7) is set to 1.
0xDD 7-0
ISRC2_PB1
0xDE 7-0 ISRC2_PB2
0xDF
6-0
New Data Flags
See Register 0x87 for a description.
0xE0 7-0 ISRC2_PB3
0xE1 7-0 ISRC2_PB4
0xE2 7-0 ISRC2_PB5
0xE3 7-0 ISRC2_PB6
0xE4 7-0 ISRC2_PB7
0xE5 7-0 ISRC2_PB8
0xE6 7-0 ISRC2_PB9
0xE7
6-0
New Data Flags
See Register 0x87 for a description.
0xE8 7-0 ISRC2_PB10
0xE9 7-0 ISRC2_PB11
0xEA 7-0 ISRC2_PB12
0xEB 7-0 ISRC2_PB13
0xEC 7-0 ISRC2_PB14
0xED 7-0 ISRC2_PB15
0xEE 7-0 ISRC2_PB16
AD9880
Rev. 0 | Page 56 of 64
2-WIRE SERIAL CONTROL PORT
A 2-wire serial interface control interface is provided in the
AD9880. Up to two AD9880 devices can be connected to the
2-wire serial interface, with a unique address for each device.
The 2-wire serial interface comprises a clock (SCL) and a
bidirectional data (SDA) pin. The analog flat panel interface
acts as a slave for receiving and transmitting data over the serial
interface. When the serial interface is not active, the logic levels
on SCL and SDA are pulled high by external pull-up resistors.
Data received or transmitted on the SDA line must be stable for
the duration of the positive-going SCL pulse. Data on SDA must
change only when SCL is low. If SDA changes state while SCL is
high, the serial interface interprets that action as a start or stop
sequence.
There are six components to serial bus operation:
Start signal
Slave address byte
Base register address byte
Data byte to read or write
Stop signal
Acknowledge (Ack)
When the serial interface is inactive (SCL and SDA are high)
communications are initiated by sending a start signal. The start
signal is a high-to-low transition on SDA while SCL is high.
This signal alerts all slaved devices that a data transfer sequence
is coming.
The first eight bits of data transferred after a start signal
comprise a seven bit slave address (the first seven bits) and a
single R/W\ bit (the eighth bit). The R/W\ bit indicates the
direction of data transfer, read from (1) or write to (0) the slave
device. If the transmitted slave address matches the address of
the device (set by the state of the SA0 input pin as shown in
Table 97), the AD9880 acknowledges by bringing SDA low on
the 9th SCL pulse. If the addresses do not match, the AD9880
does not acknowledge.
Table 97. Serial Port Addresses
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
A
6
(MSB)
A
5
A
4
A
3
A
2
A
1
A
0
1
0 0 1 1 0 0
Data Transfer via Serial Interface
For each byte of data read or written, the MSB is the first bit of
the sequence.
If the AD9880 does not acknowledge the master device during a
write sequence, the SDA remains high so the master can gener-
ate a stop signal. If the master device does not acknowledge the
AD9880 during a read sequence, the AD9880 interprets this as
end of data. The SDA remains high, so the master can generate
a stop signal.
Writing data to specific control registers of the AD9880 requires
that the 8-bit address of the control register of interest be writ-
ten after the slave address has been established. This control
register address is the base address for subsequent write opera-
tions. The base address auto-increments by one for each byte of
data written after the data byte intended for the base address. If
more bytes are transferred than there are available addresses,
the address does not increment and remains at its maximum
value. Any base address higher than the maximum value does
not produce an acknowledge signal.
Data are read from the control registers of the AD9880 in a
similar manner. Reading requires two data transfer operations:
The base address must be written with the R/W bit of the slave
address byte low to set up a sequential read operation.
Reading (the R/W bit of the slave address byte high) begins at
the previously established base address. The address of the read
register auto-increments after each byte is transferred.
To terminate a read/write sequence to the AD9880, a stop signal
must be sent. A stop signal comprises a low-to-high transition
of SDA while SCL is high.
A repeated start signal occurs when the master device driving
the serial interface generates a start signal without first genera-
ting a stop signal to terminate the current communication. This
is used to change the mode of communication (read, write)
between the slave and master without releasing the serial
interface lines.
AD9880
Rev. 0 | Page 57 of 64
SDA
SCL
t
BUFF
t
STAH
t
DHO
t
DSU
t
DAL
t
DAH
t
STASU
t
STOSU
05087-007
Figure 17. Serial Port Read/Write Timing
Serial Interface Read/Write Examples
Read from one control register:
Write to one control register:
Start signal
Start signal
Slave address byte (R/W\ bit = low)
Slave address byte (R/W\ bit = low)
Base address byte
Base address byte
Start signal
Data byte to base address
Slave address byte (R/W\ bit = high)
Stop signal
Data byte from base address
Stop signal
Write to four consecutive control registers:
Read from four consecutive control registers:
Start signal
Start signal
Slave address byte (R/W\ bit = LOW)
Slave address byte (R/W\ bit = low)
Base address byte
Base address byte
Data byte to base address
Start signal
Data byte to (base address + 1)
Slave address byte (R/W\ bit = high)
Data byte to (base address + 2)
Data byte from base address
Data byte to (base address + 3)
Data byte from (base address + 1)
Stop signal
Data byte from (base address + 2)
Data byte from (base address + 3)
Stop signal
BIT 7
ACK
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
SDA
SCL
05087-008
Figure 18. Serial Interface--Typical Byte Transfer
AD9880
Rev. 0 | Page 58 of 64
PCB LAYOUT RECOMMENDATIONS
The AD9880 is a high-precision, high-speed analog device. To
achieve the maximum performance from the part, it is impor-
tant to have a well laid-out board. The following is a guide for
designing a board using the AD9880.
Analog Interface Inputs
Using the following layout techniques on the graphics inputs is
extremely important:
Minimize the trace length running into the graphics
inputs. This is accomplished by placing the AD9880 as
close as possible to the graphics VGA connector. Long
input trace lengths are undesirable, because they pick up
more noise from the board and other external sources.
Place the 75 termination resistors (see Figure 3) as close
to the AD9880 chip as possible. Any additional trace length
between the termination resistors and the input of the
AD9880 increases the magnitude of reflections, which
corrupts the graphics signal.
Use 75 matched impedance traces. Trace impedances
other than 75 also increase the chance of reflections.
The AD9880 has very high input bandwidth (300 MHz). While
this is desirable for acquiring a high resolution PC graphics
signal with fast edges, it means that it also captures any high
frequency noise present. Therefore, it is important to reduce the
amount of noise that gets coupled to the inputs. Avoid running
any digital traces near the analog inputs.
Due to the high bandwidth of the AD9880, sometimes low-pass
filtering the analog inputs can help to reduce noise. For many
applications, filtering is unnecessary. Experiments have shown
that placing a series ferrite bead prior to the 75 termination
resistor is helpful in filtering out excess noise. Specifically, the
part used was the Fair-Rite 2508051217Z0, but each application
may work best with a different bead value. Alternatively, placing
a 100 to 120 resistor between the 75 termination resistor
and the input coupling capacitor can also be beneficial.
Power Supply Bypassing
It is recommended to bypass each power supply pin with a
0.1 F capacitor. The exception is in the case where two or more
supply pins are adjacent to each other. For these groupings of
powers/grounds, it is only necessary to have one bypass
capacitor. The fundamental idea is to have a bypass capacitor
within about 0.5 cm of each power pin. Also, avoid placing the
capacitor on the opposite side of the PC board from the
AD9880, since that interposes resistive vias in the path.
The bypass capacitors should be physically located between the
power plane and the power pin. Current should flow from the
power plane to the capacitor to the power pin. Do not make the
power connection between the capacitor and the power pin.
Placing a via underneath the capacitor pads down to the power
plane is generally the best approach.
It is particularly important to maintain low noise and good
stability of PV
DD
(the clock generator supply). Abrupt changes
in PV
DD
can result in similarly abrupt changes in sampling clock
phase and frequency. This can be avoided by careful attention to
regulation, filtering, and bypassing. It is highly desirable to
provide separate regulated supplies for each of the analog
circuitry groups (V
D
and PV
DD
).
Some graphic controllers use substantially different levels of
power when active (during active picture time) and when idle
(during Hsync and Vsync periods). This can result in a
measurable change in the voltage supplied to the analog supply
regulator, which can in turn produce changes in the regulated
analog supply voltage. This can be mitigated by regulating the
analog supply, or at least PV
DD
, from a different, cleaner, power
source (for example, from a 12 V supply).
It is recommended to use a single ground plane for the entire
board. Experience has repeatedly shown that the noise perfor-
mance is the same or better with a single ground plane. Using
multiple ground planes can be detrimental since each separate
ground plane is smaller and long ground loops can result.
In some cases, using separate ground planes is unavoidable. For
those cases, it is recommend to place a single ground plane
under the AD9880. The location of the split should be at the
receiver of the digital outputs. In this case it is even more
important to place components wisely because the current
loops are much longer, (current takes the path of least
resistance). An example of a current loop is power plane to
AD9880 to digital output trace to digital data receiver to digital
ground plane to analog ground plane .
PLL
Place the PLL loop filter components as close as possible to the
FILT pin.
Do not place any digital or other high frequency traces near
these components.
Use the values suggested in the datasheet with 10% tolerances
or less.
AD9880
Rev. 0 | Page 59 of 64
Outputs (Both Data and Clocks)
Try to minimize the trace length that the digital outputs have to
drive. Longer traces have higher capacitance, which require
more current that causes more internal digital noise.
Shorter traces reduce the possibility of reflections.
Adding a series resistor of value 50 to 200 can suppress
reflections, reduce EMI, and reduce the current spikes inside of
the AD9880. If series resistors are used, place them as close as
possible to the AD9880 pins (although try not to add vias or
extra length to the output trace to move the resistors closer).
If possible, limit the capacitance that each of the digital outputs
drives to less than 10 pF. This can be easily accomplished by
keeping traces short and by connecting the outputs to only one
device. Loading the outputs with excessive capacitance increases
the current transients inside of the AD9880 and creates more
digital noise on its power supplies.
Digital Inputs
The digital inputs on the AD9880 were designed to work with
3.3 V signals, but are tolerant of 5.0 V signals. Therefore, no
extra components need to be added if using 5.0 V logic.
Any noise that enters the Hsync input trace can add jitter to the
system. Therefore, minimize the trace length and do not run
any digital or other high frequency traces near it.
AD9880
Rev. 0 | Page 60 of 64
COLOR SPACE CONVERTER (CSC) COMMON SETTINGS
Table 98. HDTV YCrCb (0 to 255) to RGB (0 to 255) (Default Setting for AD9880)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff 3
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x0C 0x52 0x08 0x00 0x00 0x00 0x19 0xD7
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x1C 0x54 0x08 0x00 0x3E 0x89 0x02 0x91
Register
Blue/Cb Coeff 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x00 0x00 0x08 0x00 0x0E 0x87 0x18 0xBD
Table 99. HDTV YCrCb (16 to 235) to RGB (0 to 255)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff 3
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x47 0x2C 0x04 0xA8 0x00 0x00 0x1C 0x1F
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x1D 0xDD 0x04 0xA8 0x1F 0x26 0x01 0x34
Register
Blue/Cb Coeff 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x00 0x00 0x04 0xA8 0x08 0x
75 0x1B 0x7B
Table 100. SDTV YCrCb (0 to 255) to RGB (0 to 255)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff 3
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x2A 0xF8 0x08 0x00 0x00 0x00 0x1A 0x84
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x1A 0x6A 0x08 0x00 0x1D 0x50 0x04 0x23
Register
Blue/Cb Coeff. 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x00 0x00 0x08 0x00 0x0D 0xDB 0x19 0x12
Table 101. SDTV YCrCb (16 to 235) to RGB (0 to 255)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff 3
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x46 0x63 0x04 0xA8 0x00 0x00 0x1C 0x84
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x1C 0xC0 0x04 0xA8 0x1E 0x6F 0x02 0x1E
Register
Blue/Cb Coeff 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x00 0x00 0x04 0xA8 0x08 0x11 0x1B 0xAD
AD9880
Rev. 0 | Page 61 of 64
Table 102. RGB (0 to 255) to HDTV YCrCb (0 to 255)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x08 0x2D 0x18 0x93 0x1F 0x3F 0x08 0x00
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x03 0x68 0x0B 0x71 0x01 0x27 0x00 0x00
Register
Blue/Cb Coeff 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x1E 0x21 0x19 0xB2 0x08 0x2D 0x08 0x00
Table 103. RGB (0 to 255) to HDTV YCrCb (16 to 235)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff 3
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x07 0x06 0x19 0xA0 0x1F 0x5B 0x08 0x00
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x02 0xED 0x09 0xD3 0x00 0xFD 0x01 0x00
Register
Blue/Cb Coeff 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x1E 0x64 0x1A 0x96 0x07 0x06 0x08 0x00
Table 104. RGB (0 to 255) to SDTV YCrCb (0 to 255)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff 3
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x08 0x2D 0x19 0x27 0x1E 0xAC 0x08 0x00
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x04 0xC9 0x09 0x64 0x01 0xD3 0x00 0x00
Register
Blue/Cb Coeff 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x1D 0x3F 0x1A 0x93 0x08 0x2D 0x08 0x00
Table 105. RGB (0 to 255) to SDTV YCrCb (16 to 235)
Register
Red/Cr Coeff 1
Red/Cr Coeff 2
Red/Cr Coeff 3
Red/Cr Offset
Address
0x35 0x36 0x37 0x38 0x39 0x3A 0x3B 0x3C
Value
0x07 0x06 0x1A 0x1E 0x1E 0xDC 0x08 0x00
Register
Green/Y Coeff 1
Green/Y Coeff 2
Green/Y Coeff 3
Green/Y Offset
Address
0x3D 0x3E 0x3F 0x40 0x41 0x42 0x43 0x44
Value
0x04 0x1C 0x08 0x11 0x01 0x91 0x01 0x00
Register
Blue/Cb Coeff 1
Blue/Cb Coeff 2
Blue/Cb Coeff 3
Blue/Cb Offset
Address
0x45 0x46 0x47 0x48 0x49 0x4A 0x4B 0x4C
Value
0x1D 0xA3 0x1B 0x57 0x07 0x06 0x08 0x00
AD9880
Rev. 0 | Page 62 of 64
OUTLINE DIMENSIONS
COMPLIANT TO JEDEC STANDARDS MS-026-BED
TOP VIEW
(PINS DOWN)
1
25
26
51
50
75
76
100
0.50
BSC
LEAD PITCH
0.27
0.22
0.17
1.60 MAX
0.75
0.60
0.45
VIEW A
16.00
BSC SQ
14.00
BSC SQ
PIN 1
1.45
1.40
1.35
0.15
0.05
0.20
0.09
0.08 MAX
COPLANARITY
VIEW A
ROTATED 90 CCW
SEATING
PLANE
7
3.5
0
Figure 19. 100-Lead Low Profile Quad Flat Package [LQFP]
(ST-100)
Dimensions shown in millimeters
ORDERING GUIDE
Max Speeds (MHz)
Model
Analog
Digital
Temperature Range
Package Description
Package Option
AD9880KSTZ-100
100
100
0C to 70C
100-Lead LQFP
ST-100
1
AD9880KSTZ-150
1
150
150
0C to 70C
100-Lead LQFP
ST-100
AD9880/PCB
Evaluation
Board
1
Z = Pb-free part.
AD9880
Rev. 0 | Page 63 of 64
NOTES
AD9880
Rev. 0 | Page 64 of 64
NOTES
2005 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D0508708/05(0)
PDF 
ZIP