| 摘要 |
PURPOSE:To decrease greatly the power consumption of a phase locked loop circuit, by having an intermittent locking operation through said loop circuit of a frequency synthesizer and at the same time cutting off the power supply to an optional circuit in the nonlocking mode. CONSTITUTION:A switch 7 is provided to a phase locked loop circuit to open/ close the loop, and at the same time a switch 9 is provided to turn on and off the power supply to at least one of the circuits except a voltage control oscillator 2 among the circuits forming the loop. A storage circuit 11 stores the control voltage. A frequency monitoring means is set to a radio device which is opposite to a radio device containing the circuit 6. Then the switches 7 and 9 are closed to perform a locking operation when a frequency change exceeds a prescribed range. Then the circuit 6 performs an intermittent locking operation. As a result, the power consumption is reduced. |
