3/39

LC74731W, LC74732W

Pin Functions

Pin No.

Pin

Function

Description

Ground

Ground connection. (Digital system ground)

2

Xtalin

Crystal oscillator connections

Connections for the crystal element and capacitors that form the internal sync signal generating

3

Xtalout

crystal oscillator. Xtalin can also be used to input an external clock signal. (2fsc or 4fsc)

4

CTRL1

Switches the crystal oscillator Selects external clock input mode or crystal oscillator mode. Low: crystal oscillator mode, high:

input

external clock input mode.

5

OSCin

LC oscillator connections

Connections for the coil and capacitor that form the character output dot clock generation oscillator.

6

OSCout

This is an active-low input with hysteresis characteristics (MORE+).

When low, the

7

MUTE

Muting control input

CVout, Yout, and Cout outputs are set to either,

(1)

CSYNC,

CSYNC,

PE, or

(2)

PE

PE,

PE.

In the initial state, (1) is selected. This setting is switched by commands.

8

CDLR

Background color phase

Connection for the resistor used to adjust the background color phase

adjustment

Outputs the result of the judgment as to whether or not the external sync signal is present.

9

SYNCJDG

External sync signal judgment A high level is output when a sync signal is present.

/Rout

output (Rout output)

The dot clock (LC oscillator) is output when RST is low.

(The IC can be set up to not output this signal during resets by commands.)

10

CHARA/Gout

Character output

Character signal output

(Gout output)

11

BLANK/Bout

Blank output (Bout output)

Blank signal output pin

12

IEout/BLKout

Internal/external output

Internal synchronization (high)/external synchronization (low) state output pin

(BLKout output)

13

OUTMOD

Output switching input

Switches between output from pins 9 to 12 and input to pin 32.

Low: normal operation, high: RGB output supported

Serial data input enable

14

CS

Enable input

Serial data input is enabled when low.

more+ (Hysteresis input characteristics)

15

SIN

Data input

Serial data input

more+ (Hysteresis input characteristics)

16

SCLK

Clock input

Serial data input clock input

more+ (Hysteresis input characteristics)

17

Power supply

Composite video signal level adjustment power supply. (Analog system power supply)

18

COUT

Color signal output

Color (C) signal output

19

NC

This pin must either be left open or connected to ground.

20

CIN

Color signal input

Color (C) signal input

21

CBIAS

Chrominance bias output

Chrominance signal bias level output

22

NC

This pin must be either left open or connected to ground.

23

YOUT

Luminance signal output

Luminance signal (Y) output

24

NC

This pin must be either left open or connected to ground.

25

YIN

Luminance signal input

Luminance signal (Y) input

26

Ground

Ground

27

CVOUT

Video signal output

Composite video signal output

28

NC

This pin must either be left open or connected to ground.

29

CVIN

Video signal input

Composite video signal input

30

CVCR

Video signal input

SECAM chrominance signal input

31

HFTin

Halftone signal input

Halftone signal input

32

SYNin

Sync separator circuit input

Video signal input to the internal sync separator circuit

33

SEPout

Composite sync signal output Composite sync signal output from the internal sync separator circuit

34

SEPin

Vertical sync signal input

Vertical sync signal input

MORE+ (Hysteresis input characteristics)

35

RST

Reset input

System reset input

A built-in pull-up resistor can be included in this pin’s input circuit. (Hysteresis input characteristics)

36

Power supply (+5 V)

Power supply (+5 V: digital system power supply)

Continued on next page.