| 摘要 |
PROBLEM TO BE SOLVED: To provide a video display device equipped with a PLL circuit capable of supplying stable clocks even to the signal of a video system having a horizontal synchronizing signal inserted with an equivalent pulse or slit pulse or to the signal of a video system by which the horizontal synchronizing signal is eliminated during a vertical fly-back period, without special sequence control. SOLUTION: While using an equivalent pulse mask circuit 19 for masking the equivalent pulse and the slit pulse and a phase comparator 19 capable of stopping the operation of phase comparison during a vertical synchronizing period, the PLL circuit capable of supplying stable clocks even to irregular horizontal synchronizing signals inputted during the vertical fly-back period is constituted.
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