Load-adaptive class-G amplifier for low-power audio applications

摘要

The present invention provides a class-G amplifier, wherein the class-G amplifier includes an amplifier stage, an impedance detector and a power source. In the operations of the class-G amplifier, the amplifier stage is supplied by a supply voltage, and amplifies an input audio signal to generate an output audio signal, and the impedance detector is configured to detect an output impedance of the amplifier stage to generate a detection result, and the power source refers to the detection result to determine a level and a switching frequency of the supply voltage.