Patent ID: 9602056
Date: 2017-03-21
CPC Classifications: H03F

Claim:
1. A power amplifier module for an radio frequency communications circuit, the module comprising: a driver stage amplifier having an input that receives an radio frequency signal, the driver stage amplifier powered by a supply voltage which is applied across first and second nodes of the driver stage amplifier to amplify the radio frequency signal; a final stage amplifier that receives an amplified radio frequency signal from an output of the driver stage amplifier on the first node, that is powered by a supply voltage applied across the final stage amplifier, and that provides an amplified output signal, a bias current applied to the input of the final stage amplifier and applied to the second node to power the driver stage amplifier to reduce the current that flows through the driver stage amplifier; and an envelope tracking module that provides power to at least one of the driver stage amplifier and final stage amplifier.