Patent ID: 8107903

Claim:
A circuit comprising: a power amplifier to receive a radio frequency (RF) input signal and to transmit an RF output signal; a variable voltage generator coupled with the power amplifier, to variably provide the power amplifier with a voltage at a selected one of a plurality of voltage levels; and a control module coupled with the power amplifier and the variable voltage generator, the control module configured to receive a sample of the RF output signal, receive an RF power level control that corresponds to a desired total forward power value of the circuit, and control the variable provision of the voltage to the power amplifier by the variable voltage generator, to affect forward power of the power amplifier, based at least in part on the sample and the RF power level control, wherein the control module is configured to control the variable provision of the voltage by being configured to control the variable voltage generator to provide the voltage at a first level to satisfy the desired total forward power value in a matched condition in which an effective output impedance is matched with an input impedance of a load, the first level to further provide voltage headroom for provision of the voltage at a second level; detect, based at least in part on the sample, a mismatched condition in which the effective output impedance does not match the input impedance of the load; and provide the voltage at the second level to satisfy the desired total forward power value based at least in part on detection of the mismatched condition.