To provide an oscillation circuit that can reduce power consumption.
The oscillation circuit includes: an analog/digital conversion circuit 100 for converting an analog component included in an input signal to a digital signal; a bandpass filter 101 for passing only a preset frequency band component of the digital signal D1 converted in the analog/digital conversion circuit 100 as a reference signal; and a PLL circuit 200 for oscillating a voltage-controlled oscillator 203 disposed in a PLL loop by such feedback control as to keep a constant phase difference between the reference signal D2 passed through the bandpass filter 101 and an output signal D3 from the voltage-controlled oscillator 203. The bandpass filter 101 includes a masking section 102 for executing a masking process of fixing to "0" a predetermined bit width of the digital signal D1 converted in the analog/digital conversion circuit 100 on a predetermined condition.
Keishin Terayama
Hiroyuki Miyoshi
Ichitaro Ito