Patent ID: 7230997

Claim:
A semiconductor integrated circuit for communication comprising: a modulation circuit for performing phase modulation and amplitude modulation; a phase detection circuit for detecting a phase component of a signal modulated by said modulation circuit; an amplitude detection circuit for detecting an amplitude component of the signal modulated by said modulation circuit; a power amplifier for amplifying the power of a transmission signal and outputting the amplified transmission signal; a feedback path for feeding a signal corresponding to an output level of said power amplification circuit back to said amplitude detection circuit; a variable gain amplification circuit provided on a forward path between said amplitude detection circuit and said power amplification circuit for generating a control voltage for an amplitude control; a loop filter for setting a frequency bandwidth of an amplitude control loop, said amplitude control loop including said feedback path and said forward path; and a sequence control circuit for sequentially generating control signals and supplying the generated control signals to associated circuits for operating said circuits in a predetermined order based on a command supplied thereto.