A horizontal synchronizing signal separation circuit for a display apparatus.

摘要

The horizontal synchronizing signal seperation circuit extracts pulses indicative of horizontal synchronizing timing from a composite synchronizing signal which includes a horizontal synchronizing signal and a vertical synchronizing signal. When detecting the rising edge of the composite synchronizing signal, a rising edge detection circuit generates a pulse signal. A counter counts the number of the pulses in a clock signal. The output of the counter is supplied to a decoder which decodes the output of the counter and outputs timing signals. Using the timing signals, a control signal is generated to control a gate to which the output of the rising edge detection circuit is supplied. The output of the gate is used for generating a separated horizontal synchronizing signal. <IMAGE>