US 12,395,127 B2
Audio amplifier with feedback control
Isaac Y. Chen, Hsinchu (TW)
Assigned to Elite Semiconductor Microelectronics Technology Inc., Hsinchu (TW)
Filed by Elite Semiconductor Microelectronics Technology Inc., Hsinchu (TW)
Filed on Nov. 29, 2022, as Appl. No. 18/071,581.
Prior Publication US 2024/0178796 A1, May 30, 2024
Int. Cl. H03F 3/217 (2006.01); H03F 1/02 (2006.01)
CPC H03F 1/0205 (2013.01) [H03F 3/217 (2013.01); H03F 3/2173 (2013.01); H03F 2200/03 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An audio amplifier, comprising:
a plurality of power stages, wherein the plurality of power stages are coupled in parallel with each other, each of the plurality of power stages comprises a first switch and a second switch, the first switch and the second switch are coupled in series between a first reference voltage and a second reference voltage, and the first reference voltage is higher than the second reference voltage;
a driving circuit, coupled to the plurality of power stages, and arranged to receive an input signal, and generate a driving signal to the plurality of power stages according to the input signal for driving the plurality of power stages;
a power stage control circuit, comprising:
a feedback circuit, coupled to the plurality of power stages, and arranged to generate a feedback signal according to at least one detection input, wherein the at least one detection input comprises at least one of a power of the first reference voltage, a voltage signal corresponding to a switching time of the plurality of power stages, and a voltage signal corresponding to a switching frequency of the plurality of power stages; and
a control circuit, coupled between the feedback circuit and the plurality of power stages, and arranged to generate a control signal according to the feedback signal, wherein the control signal is arranged to dynamically control a number of turned-on power stages in the plurality of power stages.