Spread spectrum clock generator, electronic apparatus, and spread spectrum clock generation method

Abstract

A spread spectrum clock generator includes a phase comparator that compares a reference clock with a feedback clock, a low-pass filter that passes a predetermined low-frequency component, a phase lock loop that includes a voltage-controlled oscillator generating an output clock whose frequency corresponds to the filtered signal, a triangular wave controller that generates a triangular wave signal for frequency-modulating the spread spectrum clock based on the output clock, a delay controller that generates the feedback clock by controlling delay of the output clock based on the triangular wave signal, a first counter that counts the output clock and output a first count value, a second counter that counts the reference clock and output a second count value, and a phase error correction circuit that compares the first count value with the second count value and corrects phase error of the output clock.