LM1292

LM1292 Video PLL System for Continuous-Sync Monitors April 1999 LM1292 Video PLL System for Continuous-Sync Monitors General Description The LM1292 is a very low jitter, integrated horizontal time base solution specifically designed to operate in high performance, continuous-sync video monitors. It automatically synchronizes to any H frequency from 22 kHz to 125 kHz and provides the drive pulse to the high power deflection circuit. Available sync processing includes a vertical sync separator and a composite video sync stripper. An internal sync selection scheme gives highest priority to separate H and V sync, then composite sync, and finally sync on video; no external switching between sync sources is necessary. The LM1292 provides polarity-normalized H/HV and V sync outputs. The LM1292 design uses an on-chip FVC (Frequency-to-Voltage Converter) to set the center frequency of the VCO (Voltage-Controlled Oscillator). This technique allows autosync operation over the entire frequency range using just one optimized set of external components. The system includes a second phase detector which compensates for storage time variation in the horizontal output transistor; the picture’s horizontal position is thus independent of temperature and component variance. The LM1292 provides DC control pins for H Drive duty cycle and flyback phase. Features n Wide continuous autosync range — 22 kHz–125 kHz (1:5.7) with no component switching or external adjustments n No manufacturing trims ...