Pin Descriptions

Pin

Pin

Schematic

Description

No.

Name

1

2

3

Red OSD Input

Green OSD Input

Blue OSD Input

These inputs accept standard TTL inputs. Each color is either

fully on (logic high) or fully off (logic low). Connect unused

pins to ground with a 47k resistor.

4

Video/OSD Switch

This input accepts a standard TTL input.

H = OSD

L = Video

Connect to ground with a 47k resistor when not using OSD.

5

8

11

Red Video In

Green Video In

Blue Video In

Video inputs. These inputs must be AC Coupled with a

minimum of a 1 µF cap, 10 µF is perferred. DC restoration is

done at these inputs. A series resistor of about 33

Ω should

also be used.

6

9

V

CC1

Power supply pins (excluding output stage)

7

10

21

Ground

Ground pins. All grounds are internally connected and must

also be connected on the PCB.

12

V

REF

Pin used for additional filter capacitor to internal reference.

The voltage at this pin is 2.0V.

13

14

26

27

28

Video Contrast

OSD Contrast

Blue Drive

Green Drive

Red Drive

Contrast control pins:

4V — no attenuation

0V — over 60 dB attenuation

Drive control pins:

4V — no attenuation

0V — 12 dB attenuation

15

16

Clamp Gate

Blank Gate

Both pins accept TTL inputs and are active low. The clamp

gate provides DC restoration of the video signal. The blank

gate forces the video outputs to below 200 mV.

17

19

24

Blue Clamp Cap

Green Clamp Cap

Red Clamp Cap

The external clamp cap is charged and discharged to the

correction voltage needed for DC restoration. 0.1 µF is the

recommended value.

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