Patent attributes
An envelope tracking (ET) amplifier circuit is provided. The ET amplifier circuit includes an ET voltage circuit configured to generate an ET modulated voltage based on a supply voltage for amplifying a radio frequency (RF) signal. The ET modulated voltage corresponds to a time-variant voltage envelope, which can be misaligned from a time-variant signal envelope of the RF signal due to an inherent temporal delay in the ET amplifier circuit. A voltage processing circuit is provided in the ET amplifier circuit to reduce dynamic range of the ET modulated voltage to help improve delay sensitivity in the ET amplifier circuit. A control circuit is configured to reduce the supply voltage according to the dynamic range to help maintain system-wide efficiency of the ET amplifier circuit at a defined level. As such, it may be possible to improve delay sensitivity and maintain sufficient system-wide efficiency in the ET amplifier circuit.
