OUT OF CLOCK SYNCHRONISM DETECTING CIRCUIT

摘要

PURPOSE:To detect out of synchronizing stably at all time by avoiding mis- detection of out of synchronism caused by the deterioration of the C/N of reception data or the like without use of a low pass filter requiring adjustment of a cut-off frequency. CONSTITUTION:A multiplier 53 extracting a clock component being a reference signal used to match the synchronization of a reproduced clock outputted from a voltage controlled oscillator 7 is actuated by demodulation data inputted from an input terminal 1. On the other hand, a multiplier 3 extracting the clock component from identification data obtained from eliminating fluctuation in the demodulation data with a D flip-flop 2 is provided and the clock component is directly inputted to a data terminal D of the D flip-flop 5 detecting out of synchronism of the reproduced clock.