| 摘要 |
<p>PURPOSE:To effectively detect the synchronizing signal of a rectangular wave by providing a second rectangular wave signal detecting means for outputting the rectangular wave signal obtained by either one of a sampling clock signal of 1/2 or the inverse signal thereof based on a signal from a pattern detecting control means. CONSTITUTION:A first rectangular wave signal detecting means 1 to which an analog signal is inputted detects the pattern of the rectangular wave signal cyclically included in the analog signal. The second rectangular wave signal detecting means 2 has substantially the same constitution as the first rectangular wave signal detecting means and based on a detecting signal from the pattern detecting control means 3, either one of the rectangular wave signal obtained in the 1/2 sampling clock signal or the rectangular wave signal obtained by the inverse signal of the 1/2 sampling clock signal is outputted. Thereby, even when the synchronizing signal of the rectangular wave included in the input analog signal is different from the sampling clock signal in a synchronizing circuit in phase, the synchronizing signal of the rectangular wave is stabilized and effectively detected.</p> |
