| 摘要 |
PROBLEM TO BE SOLVED: To provide the phase detecting device which provides equivalent electric charges for a loop almost under in-phase conditions. SOLUTION: A phase detector circuit 500 is equipped with a 1st flip-flop 502, a 2nd flip-flop 504, a 1st charge pump 506, and a 2nd charge pump 508. One flip-flop enables the charge pump directly in response to a received time signal. A 1st delay circuit 512 delays the output signal from the 1st flip-flop 502 to an AND gate 510 putting together a delayed output signal and the output signal from the 2nd flip-flop 504. The output of the AND gate is delayed by a 2nd delay circuit 514 to generate a delayed reset signal. This reset signal resets both the flip-flops at the same time to disable the charge pump. The phase detector circuit 500 balances the quantity of electric charges given to the phase-locked loop almost under in-phase conditions to improve the linearlity of the phase detector. |
