| 摘要 |
PROBLEM TO BE SOLVED: To generate a phase difference of input and output signals with high precision without using a current source of a very small current and to eliminate the dependence of the phase difference onto an input frequency. SOLUTION: A phase difference generating current I1 is added to either of a charge-up current Iup and a charge-down current Idown switched by a phase comparator circuit 7 of a charge pump circuit 9a charging up/charging down a loop filter 12 controlled by an output signal D of the phase comparator circuit 7 for each period, and a phase difference τd is generated between input output signals A and B whose phases are compared. The phase difference τd is changed with a period when the current I1 flows and the period is specified by an output of a monostable multivibrator 9a. |
