Patent ID: 7683723

Claim:
A multi-band type semiconductor circuit device which adjusts a plurality of frequency bandwidths, comprising: a base band; a transmitter circuit; a receiver circuit; and a synthesizer block changing a division ratio, wherein an output signal of said receiver circuit is inputted to said base band, wherein an output signal of said base band is inputted to said transmitter circuit, and the output signal of said base band is modulated to a first reference signal by an I/Q modulator of said transmitter circuit, wherein said synthesizer block supplies a signal as a local clock, and varies a frequency of an input clock signal from a crystal oscillator to said transmitter circuit and said receiver circuit, wherein said transmitter circuit includes an offset PLL transmitter, and wherein said offset PLL transmitter comprises a first voltage locked oscillator; a first frequency conversion circuit, with which an output of said first voltage locked oscillator is connected; a first phase detector, having a first input at a first input side with which an output of said first frequency conversion circuit is connected and a second input selectively connected to a first reference signal or an output signal of a first signal source; a first charge pump circuit, with which an output of said first phase detector is connected; a first loop filter, with which an output of said first charge pump circuit is connected; a first counter which is connected with an output of said first voltage locked oscillator; a first integrator, which is connected with an output of said first counter; and a controller, which detects loop characteristics of said offset PLL transmitter based on a result of detection of said first integrator and which performs feedback of the result of detection on a value of the charge pump current, wherein said local clock is inputted to said first frequency conversion circuit of said transmitter circuit, and wherein said loop characteristics is detected by varying the frequency of said output signal of said first signal source.