Document No. 520 - 38 - 3

GT4123, GT4123A

Two Channel Video Multipliers

GENNUM CORPORATION P.O. Box 489, Stn A, Burlington, Ontario, Canada L7R 3Y3

tel. (905) 632-2996 fax: (905) 632-5946

Japan Branch: A-302, M i yamae Vi l l age, 2–10–42 M i yamae, Suginami–ku Tokyo 168, Japan

tel. (03) 3334-7700

fax (03) 3247-8839

DATA SHEET

DESCRIPTION

The GT4123 and GT4123A are monolithic dual-channel

video multipliers for use in a wide range of applications

including broadcast and multimedia.

Featuring two wideband video inputs and a single control

input, they achieve high quality video mixing of the two

video input signals to a single output by implementing the

function:

V

O

= [ ( V

C

• V

A

) + (1 - V

C

) • V

B

]

where V

C

is the control input voltage, which may be varied

continuously over the range 0 to 1V with respect to the

ground pin, and V

A

and V

B

are the video input signals.

The GT4123 operates with typical power supply voltages

of

±10 volts and draws 15 mA of current. The GT4123A

typically operates from +12 and -5 volt supplies. Both are

available in 8 pin PDIP and 8 pin SOIC.

An Application Note entitled "Using the GT4123 and GT4123A

Video MIxer ICs" (Document No. 520 - 61) is available from

Gennum Corporation.

FEATURES

• two-quadrant video multiplication

• 20 MHz 0.1 dB video & control channel bandwidth

• one external frequency compensation adjustment

• ultra low differential gain & differential phase

• convenient 8 pin package

APPLICATIONS

• Multimedia Graphics Overlay

• Production switchers

• Linear Keyers

V

cc

VIDEO IN A

VIDEO IN B

OUTPUT

FREQ. COMP

CONTROL

GROUND

8 PIN DIP

V

EE

4

5

8

PIN 1

TOP VIEW

PIN CONNECTIONS

Part Number

Package Type

Temperature Range

GT4123 - CDA

8 pin PDIP

GT4123 - CKA

8 pin SOIC

GT4123ACDA

8 pin PDIP

GT4123ACKA

8 pin SOIC

ORDERING INFORMATION

VIDEO IN A

OUTPUT

(INTERNAL)

FREQ

COMP

VIDEO IN B

CONTROL

MULTIPLIER

CORE

FUNCTIONAL BLOCK DIAGRAM

CAUTION

ELECTROSTATIC

SENSITIVE DEVICES

DO NOT OPEN PACKAGES OR HANDLE

EXCEPT AT A STATIC-FREE WORKSTATION

Revision Date: January 1994.