| 摘要 |
PROBLEM TO BE SOLVED: To provide a video display device with a switching power source, on which a tuner stably displaying a satisfactory image in which the beat by the switching power source is suppressed is mounted. SOLUTION: The video display device is constituted by providing a CR oscillator 17a and a PLL (phase locked loop) circuit 29 which outputs a frequency signal of a half of integral multiple of a horizontal synchronizing frequency signal as a means for inputting a frequency signal in a triangular wave generation circuit 17b, when a synchronizing separation circuit 33 detects the horizontal synchronizing signal, the frequency signal from the PLL circuit 29 is transmitted to the triangular wave generation circuit 17b, and when the horizontal synchronizing signal is not detected, the frequency signal from the CR oscillator 17a or the frequency signal outputted from the PLL circuit 29 immediately before detection of the horizontal synchronizing signal becomes disabled, is transmitted to the triangular wave generation circuit 17b. COPYRIGHT: (C)2004,JPO&NCIPI
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