| 摘要 |
<p>Provided is a video signal processing device capable of judging the viability of phase locking at a PLL circuit and, in accordance with the judgment, automatically switching between the PLL circuit and a DLL circuit to use to generate a sampling clock of an input analog video signal, the device including an AD converter for AD converting an analog video signal, and a clock signal generating circuit for supplying a clock signal to the AD converter. The clock signal generating circuit includes: a PLL circuit for generating a first clock signal on the basis of a horizontal synchronous signal acquired from the analog video signal; a DLL circuit for generating a second clock signal on the basis of a composite synchronous signal acquired from the analog video signal; and a clock selecting portion for selecting and outputting either the first clock signal or the second clock signal on the basis of output of a PLL-dedicated phase comparator.</p> |
