LM2476

Monolithic Triple Channel 6.5 ns High Gain CRT Driver

and Bias Clamp

General Description

The LM2476 is a monolithic triple channel CRT driver and

triple bias clamp for low-cost color monitor applications. The

highly integrated IC contains three wide-band amplifiers for

driving the RGB cathodes of a CRT through external cou-

pling capacitors and three low-band clamp amplifiers for DC

restoration and cutoff adjustment of the video outputs. The

CRT drivers have a high, fixed gain of -27 and can drive CRT

capacitive loads as well as resistive loads present in other

applications, limited only by the package’s power dissipation.

The IC is packaged in a 19-lead TO-247 molded plastic

package and must be operated with a properly chosen heat

sink. See the Package Mounting and Thermal Consider-

ations sections for more information.

Features

n

Well-matched to the LM123X/4X family of preamplifiers

n

Operates with V

n

Convenient TO-247 staggered lead package style

CRT Drivers

n

High gain of –27 for up to 60V

n

Stable with capacitive loads and inductive peaking

networks

Bias Clamps

n

Gain of –17 for up to 60V DC output range

Applications

n

1024 x 768 displays up to 85 Hz refresh rate

n

Pixel clock frequencies up to 95 MHz

n

Monitors using video blanking

Pinout Diagram and Pin Descriptions

Pin Name

Pin Description

IND

Driver Input Pins (1, 3, 4)

INC

Clamp Input Pins (6, 7, 8)

V

BB

Bias Voltage Pin (2)

V

CC

Supply Voltage Pin (14)

GND*

Ground Pins (5, 10, 12, 16, 18)

OUTC

Clamp Output Pins (9, 11, 13)

OUTD

Driver Output Pins (15, 17, 19)

*Note: All GND pins should be connected together via low HF impedance

traces on the PCB.

20121901

Note: Tab is at GND

FIGURE 1. Pinout and Connection Diagram

January 2004

© 2005 National Semiconductor Corporation

DS201219

www.national.com