EFFICIENT PARALLEL-STAGE POWER AMPLIFIER

摘要

An amplifier circuit (40) for providing an amplified signal in response to a n input signal. The amplifier circuit (40) includes an input network (44) for applying the input signal to a selected at least one of a plurality of amplifier stages. An output network (48) is provided for coupling the amplified signal from the selected at least one amplifier stage . The appropriate amplifier stage is selected by a control circuit (56) in response to a desired power value of the amplified signal. By selectively activating only the amplifier stages) that is/are necessary to provide the desired level of output power, increased DC efficiency can be accomplished in applications that require an amplifier which operates linearly over a wide dynamic range.