POWER AMPLIFICATION MODULE

摘要

The present invention improves power efficiency when an envelope tracking system is adopted for a power amplification module that is compatible with multiple frequency bands. This power amplification module is equipped with multiple power amplification circuits, each equipped with: a first transformer that includes a first input-side winding, to which a radio frequency signal is input, and a first output-side winding that is electromagnetically coupled with the first input-side winding; a first differential amplification circuit that includes a first transistor, to which a first radio frequency signal output from one end of the first output-side winding is input through a control electrode thereof, and a second transistor, to which a second radio frequency signal output from the other end of the first output-side winding is input through a control electrode thereof, said first differential amplification circuit outputting a first amplified signal that is obtained by amplifying the difference between the first and second radio frequency signals; and a second transformer that supplies a source voltage, which fluctuates in accordance with the amplitude of the radio frequency signal, to the first differential amplification circuit and that includes a second input-side winding, to which the first amplified signal is input, and a second output-side winding that is electromagnetically coupled with the second input-side winding.