| 摘要 |
PURPOSE:To obtain an output signal corresponding to an input signal even when there is no input signal by providing a device that switches and selects an output of a circuit that stores the controlled voltage of the controlled voltage oscillator of a phase synchronizing oscillator and an output of a loop filter. CONSTITUTION:An phase comparator 1 compares phases of an input signal and output signal of a voltage controlling oscillator 3 with each other, and controls the oscillator 3 by the control voltage of the output passed through a loop filter 2 and a switch 6. This control voltage is converted to a digital signal by an A/D converter at optional timing from a control circuit 5d and stored in a memory 5b. When there is no input signal, the digital signal stored in the memory 5b is converted to analog voltage by the A/D converter 5c and the voltage is given to the oscillator 3 by changing over the switch 6. By this way, output signals corresponding to input signals at any timing can be obtained. |
