SN74ALVCH16821
3.3-V 20-BIT BUS-INTERFACE FLIP-FLOP
WITH 3-STATE OUTPUTS
SCES037C JULY 1995 REVISED FEBRUARY 1999
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D
Member of the Texas Instruments
Widebus
TM
Family
D
EPIC
TM
(Enhanced-Performance Implanted
CMOS) Submicron Process
D
ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
D
Latch-Up Performance Exceeds 250 mA Per
JESD 17
D
Bus Hold on Data Inputs Eliminates the
Need for External Pullup/Pulldown
Resistors
D
Package Options Include Plastic 300-mil
Shrink Small-Outline (DL) and Thin Shrink
Small-Outline (DGG) Packages
description
This 20-bit bus-interface flip-flop is designed for
1.65-V to 3.6-V V
CC
operation.
The SN74ALVCH16821 can be used as two 10-bit
flip-flops or one 20-bit flip-flop. The 20 flip-flops
are edge-triggered D-type flip-flops. On the
positive transition of the clock (CLK) input, the
device provides true data at the Q outputs.
A buffered output-enable (OE) input can be used
to place the ten outputs in either a normal logic
state (high or low logic levels) or the
high-impedance state. In the high-impedance
state, the outputs neither load nor drive the bus
lines significantly. The high-impedance state and
increased drive provide the capability to drive bus
lines without need for interface or pullup
components.
OE does not affect the internal operation of the flip-flops. Old data can be retained or new data can be entered
while the outputs are in the high-impedance state.
To ensure the high-impedance state during power up or power down, OE should be tied to V
CC
through a pullup
resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.
Active bus-hold circuitry is provided to hold unused or floating data inputs at a valid logic level.
The SN74ALVCH16821 is characterized for operation from 40
C to 85
C.
Copyright
1999, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
DGG OR DL PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
1OE
1Q1
1Q2
GND
1Q3
1Q4
V
CC
1Q5
1Q6
1Q7
GND
1Q8
1Q9
1Q10
2Q1
2Q2
2Q3
GND
2Q4
2Q5
2Q6
V
CC
2Q7
2Q8
GND
2Q9
2Q10
2OE
1CLK
1D1
1D2
GND
1D3
1D4
V
CC
1D5
1D6
1D7
GND
1D8
1D9
1D10
2D1
2D2
2D3
GND
2D4
2D5
2D6
V
CC
2D7
2D8
GND
2D9
2D10
2CLK
EPIC and Widebus are trademarks of Texas Instruments Incorporated.
SN74ALVCH16821
3.3-V 20-BIT BUS-INTERFACE FLIP-FLOP
WITH 3-STATE OUTPUTS
SCES037C JULY 1995 REVISED FEBRUARY 1999
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
FUNCTION TABLE
(each 10-bit flip-flop)
INPUTS
OUTPUT
OE
CLK
D
Q
L
H
H
L
L
L
L
H or L
X
Q0
H
X
X
Z
logic symbol
1Q1
2
1Q2
3
1Q3
5
1Q4
6
1Q5
8
1Q6
9
1Q7
10
1Q8
12
1Q9
13
1Q10
14
2Q1
15
2Q2
16
2Q3
17
2Q4
19
2Q5
20
2Q6
21
2Q7
23
2Q8
24
2Q9
26
2Q10
27
1OE
EN2
1
56
1CLK
1D
55
1D1
54
1D2
52
1D3
51
1D4
49
1D5
48
1D6
47
1D7
45
1D8
44
1D9
43
1D10
3D
42
2D1
41
2D2
40
2D3
38
2D4
37
2D5
36
2D6
34
2D7
33
2D8
31
2D9
30
2D10
EN4
28
29
2CLK
2OE
C1
C3
2
4
This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
SN74ALVCH16821
3.3-V 20-BIT BUS-INTERFACE FLIP-FLOP
WITH 3-STATE OUTPUTS
SCES037C JULY 1995 REVISED FEBRUARY 1999
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
logic diagram (positive logic)
1D1
1OE
1Q1
1CLK
1D
To Nine Other Channels
C1
One of Ten
Channels
2D1
2OE
2Q1
2CLK
1D
To Nine Other Channels
C1
One of Ten
Channels
1
56
55
28
29
42
2
15
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage range, V
CC
0.5 V to 4.6 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range, V
I
(see Note 1)
0.5 V to 4.6 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output voltage range, V
O
(see Notes 1 and 2)
0.5 V to V
CC
+ 0.5 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input clamp current, I
IK
(V
I
< 0)
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output clamp current, I
OK
(V
O
< 0)
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous output current, I
O
50 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Continuous current through each V
CC
or GND
100 mA
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Package thermal impedance,
JA
(see Note 3): DGG package
81
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DL package
74
C/W
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range, T
stg
65
C to 150
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES:
1. The input negative-voltage and output voltage ratings may be exceeded if the input and output current ratings are observed.
2. This value is limited to 4.6 V maximum.
3. The package thermal impedance is calculated in accordance with JESD 51.
SN74ALVCH16821
3.3-V 20-BIT BUS-INTERFACE FLIP-FLOP
WITH 3-STATE OUTPUTS
SCES037C JULY 1995 REVISED FEBRUARY 1999
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
recommended operating conditions (see Note 4)
MIN
MAX
UNIT
VCC
Supply voltage
1.65
3.6
V
VCC = 1.65 V to 1.95 V
0.65
VCC
VIH
High-level input voltage
VCC = 2.3 V to 2.7 V
1.7
V
VCC = 2.7 V to 3.6 V
2
VCC = 1.65 V to 1.95 V
0.35
VCC
VIL
Low-level input voltage
VCC = 2.3 V to 2.7 V
0.7
V
VCC = 2.7 V to 3.6 V
0.8
VI
Input voltage
0
VCC
V
VO
Output voltage
0
VCC
V
VCC = 1.65 V
4
IOH
High level output current
VCC = 2.3 V
12
mA
IOH
High-level output current
VCC = 2.7 V
12
mA
VCC = 3 V
24
VCC = 1.65 V
4
IOL
Low level output current
VCC = 2.3 V
12
mA
IOL
Low-level output current
VCC = 2.7 V
12
mA
VCC = 3 V
24
t/
v
Input transition rise or fall rate
10
ns/V
TA
Operating free-air temperature
40
85
C
NOTE 4: All unused control inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
SN74ALVCH16821
3.3-V 20-BIT BUS-INTERFACE FLIP-FLOP
WITH 3-STATE OUTPUTS
SCES037C JULY 1995 REVISED FEBRUARY 1999
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
VCC
MIN
TYP
MAX
UNIT
IOH = 100
A
1.65 V to 3.6 V
VCC0.2
IOH = 4 mA
1.65 V
1.2
IOH = 6 mA
2.3 V
2
VOH
2.3 V
1.7
V
IOH = 12 mA
2.7 V
2.2
3 V
2.4
IOH = 24 mA
3 V
2
IOL = 100
A
1.65 V to 3.6 V
0.2
IOL = 4 mA
1.65 V
0.45
VOL
IOL = 6 mA
2.3 V
0.4
V
VOL
IOL = 12 mA
2.3 V
0.7
V
IOL = 12 mA
2.7 V
0.4
IOL = 24 mA
3 V
0.55
II
VI = VCC or GND
3.6 V
5
A
VI = 0.58 V
1.65 V
25
VI = 1.07 V
1.65 V
25
VI = 0.7 V
2.3 V
45
II(hold)
VI = 1.7 V
2.3 V
45
A
(
)
VI = 0.8 V
3 V
75
VI = 2 V
3 V
75
VI = 0 to 3.6 V
3.6 V
500
IOZ
VO = VCC or GND
3.6 V
10
A
ICC
VI = VCC or GND,
IO = 0
3.6 V
40
A
ICC
One input at VCC 0.6 V,
Other inputs at VCC or GND
3 V to 3.6 V
750
A
Ci
Control inputs
VI = VCC or GND
3 3 V
3.5
pF
Ci
Data inputs
VI = VCC or GND
3.3 V
6
pF
Co
Outputs
VO = VCC or GND
3.3 V
7
pF
All typical values are at VCC = 3.3 V, TA = 25
C.
This is the bus-hold maximum dynamic current. It is the minimum overdrive current required to switch the input from one state to another.
timing requirements over recommended operating free-air temperature range (unless otherwise
noted) (see Figures 1 through 3)
VCC = 1.8 V
VCC = 2.5 V
0.2 V
VCC = 2.7 V
VCC = 3.3 V
0.3 V
UNIT
MIN
MAX
MIN
MAX
MIN
MAX
MIN
MAX
fclock
Clock frequency
150
150
150
MHz
tw
Pulse duration, CLK high or low
3.3
3.3
3.3
ns
tsu
Setup time, data before CLK
4.4
3.9
3.4
ns
th
Hold time, data after CLK
0
0
0
ns
This information was not available at the time of publication.
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