LM1295 DC Controlled Geometry Correction System for Continuous Sync Monitors
April 1999
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
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Vertical scanning frequency 50 Hz鈥?70 Hz
DC controlled correction term amplitudes
Up to 125 kHz bandwidth for dynamic input signals
Minimum external parts count
Multiple IC connection for convergence applications
flexibility
Stable vertical amplitude over temperature
Compatible with the LM1291 Horizontal PLL in a H/V
system
Dynamic vertical deflection correction for second anode
high voltage drop
Both positive and negative going correction signals
Connection Diagram
DS012324-1
FIGURE 1. Order Number LM1295N
See NS Package Number N24C
漏 1999 National Semiconductor Corporation
DS012324
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