Method and apparatus for continuous-averaging counter-based digital frequency lock detector

摘要

Methods and apparatus are provided for counter-based digital frequency lock detection. A counter-based digital frequency lock detector in accordance with the present invention comprises a reference counter clocked by a reference clock and a target counter clocked by a target clock. The target counter is n bits and n is less than a number of bits of the reference counter. A frequency offset violation of the target clock is detected by comparing a value of the target counter to an n bit counter.