| 摘要 |
PROBLEM TO BE SOLVED: To provide a horizontal synchronizing signal output circuit in which disturbance of a reproduction image due to a copy guard signal is prevented through a simple arrangement even when a PLL circuit not having a mask function is used, and to provide a video reproducer comprising it. SOLUTION: The horizontal synchronizing signal output circuit comprises a synchronization separation circuit receiving a video signal, a PLL circuit receiving a composite synchronizing signal output from the synchronization separation circuit, a first timing circuit receiving a PLL output signal outputted from the PLL circuit, a second timing circuit receiving the composite synchronizing signal and a vertical synchronizing signal output from the synchronization separation circuit, and a gate circuit receiving the output signals from the first and second timing circuits and outputting the horizontal synchronizing signal of the video signal. The PLL circuit comprises an oscillation element circuit, a circuit for varying the PLL frequency of the PLL circuit, and a frequency divider wherein the output signal from the frequency divider becomes a PLL output signal. COPYRIGHT: (C)2007,JPO&INPIT
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