Patent ID: 7095260
Filing Date: 2006-08-22
Classification: H03C,H03D,H03L

Abstract:
1. A spread spectrum clock generation circuit comprising a frequency phase comparator for detecting a difference in phase between a reference clock and a generated clock, a charge pump for generating a charge/discharge signal in accordance with the difference in phase detected by the frequency phase comparator, a loop-filter for generating a differential voltage signal in accordance with the charge signal, a voltage-current conversion circuit for converting the differential voltage signal into a differential current signal, and a clock generator for generating a generated clock with a frequency in accordance with the differential current signal, wherein a spread spectrum modulation circuit for generating a spread spectrum modulation signal by modulating the differential current signal and an amplifier circuit for amplifying the spread spectrum modulation signal are comprised and the amplified spread spectrum modulation signal is added to the differential current signal and applied to the clock generator.