Patent ID: 6342819
Filing Date: 2002-01-29
Classification: H03L,H04B,H04W,Y02D

Abstract:
A frequency synthesizer device comprising:a voltage-controlled oscillator for oscillating a signal having a frequency in response to an input voltage; a first frequency divider for frequency-dividing a frequency of an output signal of the voltage-controlled oscillator; a second frequency divider for frequency-dividing a frequency of a reference signal; a phase comparator for outputting a signal of phase difference between the first frequency divider and the second frequency divider to the voltage-controlled oscillator via a low-pass filter; and a frequency-division ratio control circuit for controlling the first frequency divider such that a frequency division ratio of the first frequency divider is changed in time and a time average value contains a value below the decimal point, whereby the frequency-division ratio control circuit and at least one of other circuits are integrated on a same semiconductor substrate; wherein a means for setting a power supply voltage supplied to the frequency-division ratio control circuit lower than a power supply voltage supplied to other circuits is provided.