LM1296
Raster Geometry Correction System for Multi-Frequency
Displays
General Description
The LM1296 is a monolithic IC for use in the raster scanning
circuitry of a multi-frequency CRT monitor. The IC provides
an S-corrected sawtooth waveform and a variable DC output
voltage. These two outputs drive the vertical deflection amplifier.
It also provides another waveform for East-West geometry
correction which includes pincushion, corner, and
trapezoid controls. The geometry correction is controlled by
DC input voltages from 0V to 4V.
The raster height and the raster vertical position can be controlled
by two DC voltage input pins that adjust the sawtooth
waveform amplitude and the variable DC output voltage. The
East-West correction of the LM1296 has height tracking and
vertical position tracking capabilities. As the height or position
of the raster is adjusted the geometry correction is maintained
by the chip automatically.
The LM1296 is packaged in a 16-pin plastic DIP package.
Features
n Vertical scanning frequency 50 Hz–165 Hz
n Accepts either polarity of V sync
n DC-controlled correction terms
n Raster vertical position control
n Vertical S-correction (linearity) control
n East-West pincushion control
n East-West trapezoid control
n East-West corner control
n Provides both polarities of correction output
n East-West correction tracks raster vertical position and
height
n Compatible with LM1290 and LM1292 horizontal PLL
Applications
n Vertical deflection of monitors