Phase synchronization apparatus

PROBLEM TO BE SOLVED: To provide a phase synchronizer with which phase noise characteristic are improved by providing a phase comparator part not to generate any dead band. SOLUTION: In this phase synchronizer, three phase comparators 7B1-7B3, a delay circuit 6A2 provided at the input side of reference signal of the phase comparator 7B2 so as to input a reference signal while delaying it just for suitable delay time and a delay circuit 6A3 provided on the input side of compare signal of the phase comparator 7B3 different from the phase comparator as mentioned above so as to input a compare signal while delaying it just for suitable delay time are provided at a phase comparator part 5, and phase difference signals from these phase comparators 7B1-7B3 are respectively added by two adders 13D1 and 13D2. Then, by supplying this added phase difference signal to a charge pump 9 as a phase difference signal and transmitting it from a VCO 11, the phase synchronizer, with which the phase difference between the reference signal dividing the frequency of an oscillation signal at a prescribed frequency into reference frequency and the compare signal dividing the frequency of the output signal from the VCO 11 does not generate any dead band even near '0', is provided.