Patent ID: 9154029
Filing Date: 2015-10-06
Classification: H02M,H03F

Abstract:
1. A modulation method for an envelope tracking power supply, wherein an output of a multi-level switch regulator in the envelope tracking power supply is connected in parallel with an output of a linear regulator through an inductor, the method comprising: generating a first control signal according to a current obtained from an input first reference level signal, wherein the first reference level signal controls a change trend of an output current of the multi-level switch regulator; comparing an amplitude of a second reference level signal obtained from the first reference level signal with preset amplitudes of at least three grades of levels, outputting a second control signal according to a result of the comparison and the first control signal, wherein at least one of the preset amplitudes of at least three grades of levels is less than the amplitude of the second reference level signal and at least one of the preset amplitudes of at least three grades of levels is greater than the amplitude of the second reference level signal; outputting, by the multi-level switch regulator, a level signal with a corresponding amplitude according to the second control signal, and applying the level signal with the corresponding amplitude on the inductor to output an inductive current; and linearly adjusting, by the linear regulator, the first reference level signal to obtain a voltage output from the envelope tracking power supply to a load.