Jitter measurement circuit and jitter measurement method

A jitter measurement circuit for measuring a jitter of an input signal, the jitter measurement circuit comprising:

• a multiplexer configured to select and output one of a first comparison signal and a second comparison signal based on an output signal;
• a detecting circuit configured to output a detection signal corresponding to a phase difference between an output of the multiplexer and the input signal;
• an integrating circuit including a first input terminal connected to the detecting circuit, a second input terminal, a first output terminal and a second output terminal, and configured to amplify signals received through the first input terminal and the second input terminal and output amplified signals to the first output terminal and the second output terminal;
• a feedback circuit including a first variable capacitor connected between the first output terminal and the first input terminal and a second variable capacitor connected between the second output terminal and the second input terminal;
• and
• a comparing circuit configured to compare the signal output to the first output terminal and the signal output to the second output terminal with a reference potential to output the output signal based on a result of the comparison.

A jitter measurement method of measuring a jitter of an input signal, the jitter measurement method comprising:

• selecting one of a first comparison signal and a second comparison signal, which are clock signals, in response to an output signal;
• outputting a detection signal corresponding to a phase difference between the input signal and the selected one of the first comparison signal and the second comparison signal;
• outputting a first internal signal by summing the detection signal and a feedback signal;
• outputting a second internal signal by integrating the first internal signal;
• generating the feedback signal by trimming the second internal signal;
• and
• generating the output signal by comparing the second internal signal with a reference potential.