RF CMOS Class C Power Amplifiers for Wireless Communications

Recent efforts in the design of integrated circuits for RF communication
transceivers have focussed on achieving higher levels of integration by including more and more analog functional blocks onto a single silicon CMOS chip. One of the final blocks that has yet to be successfully integrated is the Power Amplifier (PA). The PA is the final functional block in the transmit path; its function is to amplify the signal to
be transmitted to the required transmit power level. In general, PAs are difficult to integrate in CMOS because of technology limitations that severely limit the efficiency of the PA.