Patent ID: 7499688

Claim:
A semiconductor integrated circuit device for wireless communication, comprising: a reference oscillation circuit which generates an oscillation signal in accordance with a set value from outside of the semiconductor integrated circuit device; an intermediate frequency division circuit which generates an intermediate frequency signal by dividing the oscillation signal; a frequency-division phase-shift circuit which performs frequency-dividing the intermediate frequency signal and generates orthogonal or quadrature signals with their phase being shifted by 90 degrees from each other; a modulator circuit which receives transmission signals from outside of the semiconductor integrated circuit device and the quadrature signals and outputs modulated signals; an adder circuit which synthesizes the modulated signals; and a transmission oscillation circuit which includes a phase detector, a loop filter, a transmission oscillator, a coupler and a mixer and which receives an output of the adder circuit and the oscillation signal and generates a transmission signal; wherein the reference oscillation circuit includes a reference oscillator which generates a reference oscillation signal, a programmable frequency divider which performs frequency-dividing the oscillation signal in accordance with a frequency division ratio supplied thereto, a phase comparator which detects a phase difference between an output signal of the programmable frequency divider and the reference oscillation signal, a charge pump and a filter which generate a voltage or a current based on the phase difference detected by the phase comparator, and a high frequency oscillator which generates the oscillation signal and which is controlled by the charge pump and the filter, wherein the semiconductor integrated circuit device further comprises a frequency division ratio generation circuit which generates an integer part I and a fraction part F/G based on band information concerning an externally supplied use frequency band and mode information indicative of whether signal transmission or reception and channel information as to a setup frequency, and for generating the frequency division ratio based on said integer part I and fraction part F/G, and wherein the frequency division ratio generation circuit is arranged to generate the frequency division ratio of the programmable frequency divider based on the band information, the mode information, the channel information, and externally supplied setup information as to the frequency division ratio of the programmable frequency divider.