| 摘要 |
PURPOSE:To eliminate a dead band area by applying a measured signal to two phase detection circuits, applying a reference signal to one phase detection circuit, applying a reference signal delayed at a delay line by a width of a dead band area to the other phase detection 1 circuit and adding detection outputs of the phase detection circuits. CONSTITUTION:When a phase difference between a reference signal 1A and a measured signal 1B is large, an output of a comparator 7 turns off an analog switch 8, only an output of a phase detection circuit 3A is outputted to an output terminal 10, and when the phase difference between the reference signal 1A and the measured signal 1B is small, an output of the comparator 7 turns off the analog switch 8 and a sum signal of outputs of the phase detectors 3A, 3B is outputted from the output terminal 10. |
