SM5301AS

NIPPON PRECISION CIRCUITS INC.--1

3-channel Video Buffer with Built-in Wideband Filters

OVERVIEW

The SM5301AS is a video buffer with built-in video signal bandwidth lowpass filter. The filter employs a 5-
order Butterworth lowpass filter configuration. The filter characteristics have been optimized for minimal over-
shoot and flat group delay, it has a variable cutoff frequency and guaranteed driver-stage channel gain differ-
ence and phase difference values.

FEATURES

Supply voltage: 5V

10%

VESA-standard ATSC digital TV RGB/YUV
video filters

2-system input/1-system output switching analog
multiplexer function

DC voltage level restore sync clamp function

Output buffer gain switching function: 0, 6dB
(input-to-output AC signal gain)

Channel-to-channel gain difference: 0.5dB (

supply voltage variation)

Channel-to-channel phase difference: 3.5 degree

Output signal harmonic distortion (all channels):
1.5%

Cutoff frequency: 5.8 to 37MHz variable

Package: 28-pin HSOP (Pb free)

APPLICATIONS

Set-top boxes

Digital television

DVD players

Projector

ORDERING INFORMATION

PINOUT

(Top view)

PACKAGE DIMENSIONS

(Unit: mm)

Device

Package

SM5301AS

28-pin HSOP

MUXSEL

SYNCIN

VCC4

INA

GSR1

INB

INA

GSG1

INB

INA

VFC

RFC

GND4

VCC1

OUT

GND1

VCC2

OUT

GND2

VCC3

OUT

GND3

GSB1

INB

DISABLE

GND

1.3TYP

18.6 ± 0.3

7.5 ± 0.2

9.9 ± 0.3

0.8

5.15

0.35 ± 0.05

0.12

0.10

0.1 ± 0.05

2.2 ± 0.1

0.15 0.05

+ 0.1

0.5 ± 0.2

0 to 10

SM5301AS

NIPPON PRECISION CIRCUITS INC.--3

PIN DESCRIPTION

Number

Name

I/O

Description

INA

Analog G

INA

or U

INA

signal input. Sync signal is input on SYNCIN pin.

GSG1

OUT

output buffer gain set input

INB

Analog G

INB

or U

INB

signal input. Sync signal is input on SYNCIN pin.

No connection (leave open or connect to ground)

INA

Analog B

INA

or V

INA

signal input. Sync signal is input on SYNCIN pin.

GSB1

OUT

output buffer gain set input

INB

Analog B

INB

or V

INB

signal input. Sync signal is input on SYNCIN pin.

No connection (leave open or connect to ground)

DISABLE

Power save function. Built-in pull-down resistor.
L: Enable
H: Disable (Output pins: R

OUT

, G

OUT

, and B

OUT

are high impedance.)

GND3

Analog ground

OUT

B/V signal output

VCC3

Analog 5V supply

GND2

Analog ground

OUT

G/U signal output

VCC2

Analog 5V supply

GND1

Analog ground

OUT

R/Y signal output

VCC1

Analog 5V supply

GND4

Analog ground

RFC

LPF (lowpass filter) cutoff frequency setting resistor connection

VFC

LPF (lowpass filter) cutoff frequency setting voltage input

MUXSEL

Input select signal. Built-in pull-down resistor.
L:

INA

pin select

INB

pin select

SYNCIN

Filter channel external H-Sync signal input. Active "H". Built-in pull-down resistor.

VCC4

Analog 5V supply

INA

Analog R

INA

or Y

INA

signal input. Sync signal is input on SYNCIN pin.

GSR1

OUT

output buffer gain set input

INB

Analog R

INB

or Y

INB

signal input. Sync signal is input on SYNCIN pin.

No connection (leave open or connect to ground)

SM5301AS

NIPPON PRECISION CIRCUITS INC.--4

SPECIFICATIONS

Absolute Maximum Ratings

Recommended Operating Conditions

Electrical Characteristics

= 4.5 to 5.5V, Ta = 25 to 85

C unless otherwise noted.

Parameter

Symbol

Rating

Unit

Supply voltage range

0.3 to 7.0

Storage temperature range

stg

55 to

125

Power dissipation 1

1. When mounted on a substrate: mounted on a 111

1.6mm glass-epoxy substrate with 90%

copper (Cu) wiring factor, 0m/s air flow, and Ta = 25 to 70

1.0

Power dissipation 2

2. When mounted on a substrate: mounted on a 111

1.6mm glass-epoxy substrate with 90%

copper (Cu) wiring factor, 0m/s air flow, and Ta = 70 to 80

0.9

Parameter

Symbol

Rating

Unit

Supply voltage ranges

4.5 to 5.5

Operating temperature range

25 to 85

Parameter

Symbol

Condition

Rating

Unit

Test

level

min

typ

max

Supply current 1

CC1

5.5V, RFC = 820

to GND,

VFC

0.2V (fc

5MHz),

DISABLE

"L"

100

130

Supply current 2

CC2

5.5V, RFC = 820

to GND,

VFC

1.6V (fc

40MHz),

DISABLE

"L"

120

160

Supply current 3

CC3

5.5V, RFC = 820

to GND,

VFC

0.2V (fc

40MHz),

DISABLE

"H"

2.5

Output gain error 1

Error entered around table 1 values,
Ta = 0 to 70

C, V

4.75 to 5.25V

0.5

Output gain error 2

Error entered around table 1 values,
Ta = 25 to 85

Output voltage

out2

to GND, 6dB gain setting

2.4

Vp-p

DISABLE-mode input impedance
(pull-down)

IN1

INA

, R

INB

, G

INA

INB

, B

INA

, B

INB

Clamp response time

clamp

Time for 90% output signal change
for 10mV input signal, C

0.1

Maximum input amplitude

AC coupling, 6dB gain setting

1.4

Vp-p

Maximum overshoot

2Vp-p output pulse

Maximum load capacitance

OUT

, G

OUT

, R

OUT

Output drive load

one load unit

= 150

load

Channel-to-channel gain
difference

Between R/G/B, fc/2 [Hz]

0.5

SM5301AS

NIPPON PRECISION CIRCUITS INC.--5

Filter Characteristics

= 4.5 to 5.5V, Ta = 25 to 85

°C unless otherwise noted.

Test level

I : 100% of products tested at Ta = + 25

°C.

II : Guaranteed as result of design and characteristics evaluation.

Channel-to-channel phase
difference

Between R/G/B, fc/2 [Hz]

3.5

degree

Output harmonic distortion

Vout

= 2Vp-p, f = 1MHz

1.5

Power supply rejection ratio

PSRR

= 0.5Vp-p, f = 100kHz

Output short-circuit current

100

Logic HIGH-level input voltage 1

IH1

DISABLE, MUXSEL, SYNCIN

2.5

Logic LOW-level input voltage 1

IL1

DISABLE, MUXSEL, SYNCIN

1.0

Logic HIGH-level input voltage 2

IH2

GSB1, GSG1, GSR1

- 0.5

Logic LOW-level input voltage 2

IL2

GSB1, GSG1, GSR1

0.5

Logic pull-up resistance

IN2

GSB1, GSG1, GSR1

Logic pull-down resistance

IN3

DISABLE, MUXSEL, SYNCIN

Parameter

Symbol

Condition

Rating

Unit

Test

level

min

typ

max

Cutoff frequency adjustment
range

Ta=25

°C (see figure 1)

5.8

MHz

Cutoff frequency error

= 25°C, V

= 5.0V

± 20

4fc attenuation

fIN

4fc

Output noise characteristic

NOISE

10kHz to 40MHz, 6dB output gain
setting

1.0

RMS

Crosstalk

TALK

Between 2 channels with input
0.5Vp-p 1MHz

- 47

Multiplexer crosstalk

TALK

Between MUX A

-B

- 49

Channel-to-channel group delay

Each input = 500kHz

Group delay variation

PD1

= 6.7MHz

(500kHz)

to 3.58MHz

to 4.43MHz

PD2

= 24MHz

(500kHz)

to 3.58MHz

to 4.43MHz

to 10MHz

PD3

= 36MHz

(1MHz)

to 10MHz

0.5

to 30MHz

VFC input voltage range

VFC

0.2

1.6

Parameter

Symbol

Condition

Rating

Unit

Test

level

min

typ

max

SM5301AS

NIPPON PRECISION CIRCUITS INC.--7

Figure 2. Frequency response (VFC = 0.2V)

Figure 3. Frequency response (VFC = 1.0V)

Figure 4. Frequency response (VFC = 1.6V)

8.00E+01

6.00E+01

4.00E+01

2.00E+01

0.00E+00

2.00E+01

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

Gain [dB]

Frequency [Hz]

6dB

0dB

6.00E+01

4.00E+01

2.00E+01

0.00E+00

2.00E+01

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

Gain [dB]

Frequency [Hz]

6dB

0dB

-4.00E+01

-2.00E+01

0.00E+00

2.00E+01

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

Gain [dB]

Frequency [Hz]

6dB

0dB

SM5301AS

NIPPON PRECISION CIRCUITS INC.--8

Adjusting the Cutoff Frequency

Constant-voltage control 1

Cutoff frequency control using a reference voltage VR generated by voltage divider formed by R1 and R2.

Constant-voltage control 2

Cutoff frequency control by adjusting the resistance connected to RFC.

PWM control

Cutoff frequency control by smoothing the PWM signal, using R1 and C1, input to VFC.

When VFC = 0.2V V

= 3.3V, 6% duty drive

= 5.0V, 4% duty drive

When VFC = 1.6V V

= 3.3V, 48% duty drive

= 5.0V, 32% duty drive

Note: The resistor connected to RFC can affect the cutoff frequency response, so a high-precision component

should be used. It is recommended to set the RC filter cutoff frequency to < fc/100 of the PWM wave-
form frequency.

VFC

RFC

VFC

RFC

VFC

RFC

PWM

SM5301AS

NIPPON PRECISION CIRCUITS INC.--10

TYPICAL APPLICATION CIRCUITS

ATSC Digital TV Application

(*1) Pins without an input signal, set by NUXSEL, should be left open or tied to GND.

(*2) Connect 4

× 0.1µF capacitor between the supply pins close to the IC.

(*3) Connect a 47

µF capacitor between the supply pins close to the IC.

(*4) GS

×1 are 3-level pins. Connect a capacitor if an error occurs due to external noise. Also, if open-circuit,

the internal impedance and external capacitance (C) form an RC network. When power is applied, the
open-circuit potential rises with time constant

= C × 10k (sec).

(*5) Printed circuit board supply wiring

If the supply is used for other digital circuits, there is a possibility that noise will be introduced. Accord-
ingly, these circuits should be connected to the application's analog supply.

Ground-plane wiring should be performed, as much as possible, to provide low GND line impedance.

If ground-plane wiring up to the GND pins is difficult, the ground plane should be as close to the IC as
possible with a separate wire to each GND pin.

Input Capacitor and Cutoff Frequency

The capacitor connected to pins R

INA

, R

INB

, G

INA

INB

, G

INB

, B

INA

, and B

INB

forms a highpass filter (HPF) with the internal impedance.

The HPF cutoff frequency is given by the following equation.

(C: input capacitance, R: signal input impedance = 9.3k

)

MUXSEL

SYNCIN

VCC4

INA

GSR1

INB

INA

GSG1

INB

INA

VFC

RFC

GND4

VCC1

OUT

GND1

VCC2

OUT

GND2

VCC3

OUT

GND3

GSB1

INB

DISABLE

820

Cut-off

control voltage

+5V

(*2)

(*3)

1.0

µF

1.0

µF

(*1)

(*4)

GSB1

DISABLE

(*1)

(*2)

220

µF

B/V

220

µF

R/Y

(*4)

GSG1

(*4)

GSR1

1.0

µF

SYNC

(*1)

(*2)

220

µF

G/U

fc =

SM5301AS

NIPPON PRECISION CIRCUITS INC.--11

2-load Output Connection

OUT

output 2-load connection (similarly for G

OUT

, B

OUT

outputs)

Digital TV Receiver and HDTV Decoder Box

OUT

220

µF

R/Y1

R/Y2

MPEG2

Transport/Decoder

HDTV

Decoder/Display

Processor

Graphic

Processor

D to A

Convertor

SM5301

DIGITAL TV

Video Decoder

and

Display Processor

D to A

Convertor

SM5301

RGB

MONITOR

Graphic

Processor

CAMERA

DVD-ROM MEMORY

SM5301AS

NIPPON PRECISION CIRCUITS INC.--12

NC0202BE

2003.05

Please pay your attention to the following points at time of using the products shown in this document.

The products shown in this document (hereinafter "Products") are not intended to be used for the apparatus that exerts harmful influence on
human lives due to the defects, failure or malfunction of the Products. Customers are requested to obtain prior written agreement for such
use from NIPPON PRECISION CIRCUITS INC. (hereinafter "NPC"). Customers shall be solely responsible for, and indemnify and hold NPC
free and harmless from, any and all claims, damages, losses, expenses or lawsuits, due to such use without such agreement. NPC reserves
the right to change the specifications of the Products in order to improve the characteristic or reliability thereof. NPC makes no claim or
warranty that the contents described in this document dose not infringe any intellectual property right or other similar right owned by third
parties. Therefore, NPC shall not be responsible for such problems, even if the use is in accordance with the descriptions provided in this
document. Any descriptions including applications, circuits, and the parameters of the Products in this document are for reference to use the
Products, and shall not be guaranteed free from defect, inapplicability to the design for the mass-production products without further testing
or modification. Customers are requested not to export or re-export, directly or indirectly, the Products to any country or any entity not in
compliance with or in violation of the national export administration laws, treaties, orders and regulations. Customers are requested
appropriately take steps to obtain required permissions or approvals from appropriate government agencies.

NIPPON PRECISION CIRCUITS INC.

4-3, Fukuzumi 2-chome, Koto-ku,
Tokyo 135-8430, Japan
Telephone: +81-3-3642-6661
Facsimile: +81-3-3642-6698
http://www.npc.co.jp/
Email: sales

npc.co.jp

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