PHASE LOCKED LOOP CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a phase looked loop circuit that can stably change the output frequency at a high-speed. SOLUTION: A phase comparator 4 comprises: a 1st m-multiplier 24 that receives a synchronizing signal; a 1st toggle flip-flop 22 that receives the output of the 1st m-multiplier 24; a 2nd m-multiplier 25 that receives the input signal; a 2nd toggle flip-flop 23 that receives the output of the 2nd m-multiplier 25; a 1st phase comparator 10 that receives the output of the 1st toggle flip-flop 22 and the output of the 2nd toggle flip-flop 23; a 2nd phase comparator 11 that receives the output of a 1st inverter 8 that inverts the output signal from the 1st toggle flip-flop 22 and the output of a 2nd inverter 9 that inverts the output signal of the 2nd toggle flip-flop 23; a synthesizer 12 that receives the output of the 1st phase comparator and the output of the 2nd phase comparator; and a charge pump circuit 14 that receives the output of the synthesizer 12.