| 摘要 |
<p>PURPOSE:To detect the frequency shift between a reference clock and a received clock by checking the signal pattern of the output of a comparison part periodi cally when two clocks shift in frequency. CONSTITUTION:The received clock and the clock outputted by a sampling clock generation part 310 are inputted to a series/parallel conversion part 320, which samples the received clock input with the output clock of the sampling clock generation part 310 to outputs 2n parallel signals. The 2n parallel outputs of the series/parallel conversion part 320 and the reference clock are inputted to the comparison part 350, which compares the both. If there is the shift in frequency between the both, pulses which alternate between an 'H' level and an 'L' level irregularly are outputted. Thus, the frequency shift between the two clocks can be detected with high accuracy.</p> |
