SN28837

1/2-INCH PAL TIMER

SOCS031B – JULY 1991

4

POST OFFICE BOX 655303

Terminal Functions (Continued)

TERMINAL

I/O

DESCRIPTION

NAME

NO.

I/O

DESCRIPTION

SFI

14

O

Second field index

SH1

51

O

Sample and hold 1

S1

32

O

Serial clock 1

S2

33

O

Serial clock 2

S3

34

O

Serial clock 3

T

31

O

Transfer-gate clock

TESTA

12

O

Test A (factory-test point)

TESTB

16

O

Test B (factory-test point)

TESTC

17

O

Test C (factory-test point)

VCC

24, 40, 45

DC power

VCC1

44

Oscillator power

VCR

58

I

Vertical-counter reset

VD

8

O

Vertical drive

VDS

18

I

Vertical-dump speed. When VDS is high, the vertical-dump frequency is 3.3 MHz; when VDS is low, the

vertical-dump frequency is 2 MHz.

VD2

28

O

Real-display-area signal. VD2 is a test point and is not used in normal operation.

VGATE

20

O

Decoded V count signal. VGATE is a test point and is not used in normal operation.

X1

42

Crystal oscillator (see Figure 2)

X2

43

Crystal oscillator (see Figure 2)

12

3

tint

Flush Pulses

Transfer Pulse

GP

Figure 1. GP Flush and Transfer Pulses