Low voltage frequency synthesizer using the boosting method source voltage of charge pump

摘要

PURPOSE: A low voltage frequency synthesizer is provided to prevent performance deterioration caused by a broadband, low phase noise, external environment, and process deviation by supplying the supply power of a charge pump from a voltage-controlled oscillator. CONSTITUTION: A frequency/phase detector(140) receives and compares a reference frequency and a feedback frequency and outputs comparison signal. A charge pump(110) receives the comparison signal and outputs a current that corresponds to the comparison signal. A low band pass filter(120) generates a voltage in correspondence to the output current of the charge pump. A voltage-controlled oscillator receives the message of the low band pass filter. A DC voltage converter(150) receives the boosting voltage of the voltage-controlled oscillator.