PLL CIRCUIT CAPABLE OF REDUCING OCCURRENCE OF REFERENCE LEAKAGE AND PHASE NOISE

摘要

PROBLEM TO BE SOLVED: To provide a PLL circuit capable of reducing a reference leakage and suppressing phase noise.

SOLUTION: A frequency phase comparator with switching function switches between a frequency comparison in which, based on the lock detection signal that is inputted, a rising edge of the two input signals is detected for detecting a phase difference between the two signals, and a phase comparison in which a voltage level of the two input signals is detected for detecting a phase difference between the two signals.

COPYRIGHT: (C)2012,JPO&INPIT