| 摘要 |
PROBLEM TO BE SOLVED: To eliminate phase difference between both synchronizing signals by accurately detecting the phase difference between both the synchronizing signals, without tentatively performing A/D conversion of all horizontal synchronizing signals as in the conventional cases, in a synchronizing signal processing circuit for generating an internal horizontal synchronizing signal made to synchronize with the horizontal synchronizing signal of a video signal. SOLUTION: When an internal horizontal synchronizing signal HD is generated on the basis of an internal clock signal CLK1 made to synchronize with the phase of a color burst signal included in a video signal, and also the phase difference between a horizontal synchronizing signal Hsync separated from the video signal and the signal HD is detected to perform phase control, so as to eliminate the phase difference between the both synchronizing signals Hsync and HD, this circuit is provided with a phase difference detection circuit 4, which calculates the phase difference between the signals Hsync and HD on the basis of the signals Hsync, HD, CLK1, a reverse-phase clock signal CLK2 obtained by performing level inversion of the signal CLK1 and a reference signal B for phase comparison generation, on the basis of the signal HD.
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