Patent ID: 8548398

Claim:
Radio frequency (RF) communications circuitry comprising: RF power amplifier (PA) circuitry associated with a first saturation operating constraint and adapted to: receive and amplify a first RF input signal to provide a first RF output signal; and receive an envelope power supply signal, which provides power for amplification; and control circuitry adapted to: select one of a plurality of communications modes; determine a first desired magnitude of the first RF input signal; determine a minimum allowable magnitude of the envelope power supply signal based on the first saturation operating constraint, the selected one of the plurality of communications modes, and the first desired magnitude; and restrict a magnitude of the envelope power supply signal based on the minimum allowable magnitude; and RF modulation circuitry adapted to provide the first RF input signal having approximately the first desired magnitude and having RF modulation corresponding to the selected one of the plurality of communications modes, wherein the first saturation operating constraint is based on first calibration data obtained during saturated operation of a calibration RF PA at different envelope power supply levels.