Power supply modulation method and power supply modulator

Abstract

A modulation method and modulator for an envelope tracking power supply. An output of a multi-level switching regulator () in the envelope tracking power supply modulator is in parallel connection with an output of a linear regulator () via an inductor () and supplies power to a load. The modulation method for the envelope tracking power supply includes: generating a first control signal () according to the current () obtained from inputting a first reference level signal (); comparing the amplitude of a second reference level signal () obtained according to the first reference level signal () with preset amplitudes of at least three levels, and outputting a second control signal () according to the comparison result and the first control signal (); the multi-level switching regulator () outputting a level signal of corresponding amplitude according to the second control signal (), and loading the amplitude of the level on the inductor () to output an inductive current ('); and linearly regulating the first reference level signal () via a linear regulator () to obtain a voltage output () to the load. The present disclosure resolves the problem of fixed rate of change of current output by the switching regulator of the envelope tracking power supply regulator and cannot adjust to different load current change rates, thus the inductive current outputted by the multi-level switching regulator can better track the load current change.