Apparatus and methods for envelope tracking

摘要

Apparatus and methods for envelope tracking are disclosed herein. In certain implementations, an envelope tracking system for generating a power amplifier supply voltage for a power amplifier is provided. The envelope tracking system can include a buck converter and an error amplifier configured to operate in parallel to control the voltage level of the power amplifier supply voltage based on an envelope of an RF signal amplified by the power amplifier. The buck converter can convert a battery voltage into a buck voltage that is based on an error current, and the error amplifier can generate the power amplifier supply voltage by adjusting the magnitude of the buck voltage using an output current that is based on the RF input signal's envelope. The error amplifier can control the buck converter by changing a magnitude of the error current in relation to a magnitude of the output current.

主权项

1. A mobile device comprising:
a power amplifier configured to receive a power amplifier supply voltage and to amplify a radio frequency (RF) input signal to generate an RF output signal; a buck converter configured to convert a battery voltage into a buck voltage, the buck converter configured to control a magnitude of the buck voltage based on an error current; and an error amplifier configured to generate an output current based on an envelope of the RF input signal and to generate the power amplifier supply voltage by adjusting the magnitude of the buck voltage using the output current, the error amplifier configured to control the buck converter by changing a magnitude of the error current in relation to a magnitude of the output current.