Envelope tracking modulator with feedback

摘要

There is disclosed an envelope tracking modulated supply arranged to generate a modulated supply voltage in dependence on a reference signal, comprising a low frequency path for tracking low frequency variations in the reference signal and including a switched mode power supply, a correction path for tracking high frequency variations in the reference signal and including a linear amplifier, a feedback path from the output of the linear amplifier to the input of the linear amplifier, and a combiner for combining the output of the switched mode power supply and the output of the linear amplifier to generate a modulated supply voltage.

主权项

1. An envelope tracking modulated supply arranged to generate a modulated supply voltage in dependence on a reference signal, comprising:
a low frequency path configured to receive the reference signal and track low frequency variations in the reference signal and including a switched mode power supply; a correction path configured to track high frequency variations in the reference signal and including a linear amplifier, a feedback path coupled between an output of the linear amplifier and an input of the linear amplifier, and a voltage source for providing an offset voltage in the reference signal in the correction path, wherein the voltage source is coupled to the input of the linear amplifier; and a combiner configured to combine an output of the low frequency path and an output of the correction path to generate the modulated supply voltage.