VCO (voltage-controlled oscillator) device used for a radio unit such as a
television broadcast receiver. A VCO device oscillating in a wide band of
oscillation frequency and capable of realizing low power consumption is
provided. VCO circuit group 4 oscillates signals of frequencies
corresponding to control voltage Vt applied to frequency control voltage
terminal 8. LO signal selecting means 3 selects a required output signal
from VCO circuit group 4. PLL 6 frequency-divides local signal fvco
selected by LO signal selecting means 3, compares a phase thereof with a
phase of a reference signal and outputs a signal converted from a phase
difference. Loop filter 7 smoothes the output signal from PLL 6, outputs
control voltage Vt that is a frequency control voltage and outputs the
local-signal selected by signal selecting means 3 to high frequency
signal processing means 1.