Apple Inc.
Circuit and a method for generating a radio frequency signal

Abstract:

A circuit for generating a radio frequency signal is provided. The circuit includes an amplifier configured to generate a radio frequency signal based on a baseband signal. Further, the circuit includes a power supply configured to generate a variable supply voltage based on a control signal indicating a desired supply voltage, and to supply the variable supply voltage to the amplifier. The circuit further includes an envelope tracking circuit configured to generate the control signal based on a bandwidth of the baseband signal, and to supply the control signal to the power supply.