PURPOSE: To miniaturize a device, to reduce the number of parts, and to reduce the cost by providing a frequency dividing circuit in the feedback loop of one reference frequency oscillator circuit, zero or more frequency dividing circuits, and a phase fixing loop circuit.

CONSTITUTION: A reference frequency fs is divided to fs/m by a frequency dividing circuit 102. The oscillation output signal obtained by a voltage controlled oscillating circuit 105 has the frequency divided to 1/n by a frequency dividing circuit 107 to have a frequency fo/n. A phase comparing circuit 103 compares phases of two oscillator outputs with each other, and the result is fed back to the voltage controlled oscillator circuit 105 through a low pass filter 104. Thus, the stable oscillator output whose frequency is n/m times as high as the reference frequency is obtained in an oscillator output terminal 106.