LM1295

DC Controlled Geometry Correction System for

Continuous Sync Monitors

General Description

The LM1295 is specifically designed for use in a continuous

sync monitor. The injection-locked vertical oscillator oper-

ates from 50 Hz to 170 Hz, covering all known video moni-

tors. A differential output current is provided in order to pre-

vent ground interaction.

The IC provides two outputs composed of the summation of

DC controlled 1st and 2nd order output terms. The first out-

put corrects for EW pincushion and trapezoid. The second

corrects for parallelogram and bow.

A DC controlled output is provided for vertical dynamic focus

correction.

The IC is packaged in a 24-pin narrow DIP package and op-

erates on a single 12V power supply.

Features

n Vertical scanning frequency 50 Hz–170 Hz

n DC controlled correction term amplitudes

n Up to 125 kHz bandwidth for dynamic input signals

n Minimum external parts count

n Multiple IC connection for convergence applications

flexibility

n Stable vertical amplitude over temperature

n Compatible with the LM1291 Horizontal PLL in a H/V

system

n Dynamic vertical deflection correction for second anode

high voltage drop

n Both positive and negative going correction signals

Connection Diagram

DS012324-1

FIGURE 1. Order Number LM1295N

See NS Package Number N24C

April 1999

© 1999 National Semiconductor Corporation

DS012324

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