Patent ID: 7554408

Claim:
A circuit for audio amplification, comprising: an audio amplifier having at least a first input, a second input, a VDD input, a VSS input, and an output, wherein the audio amplifier is arranged to receive an audio signal at the first input of the audio amplifier, to receive a first power supply signal at the VDD input, and to drive a speaker load at the output of the audio amplifier, wherein the audio amplifier has a process voltage with a breakdown voltage; and a converter having at least: an output that is coupled to the VSS input of the audio amplifier, and an input, wherein the converter is arranged to receive the first power supply signal at the input of the converter, and to provide a negative supply voltage at the output of the converter such that the negative supply voltage has the opposite polarity of the first supply voltage and a lesser magnitude than the first supply voltage, wherein double the first supply voltage is greater than the breakdown voltage, and such that the negative supply voltage is sufficiently smaller than in magnitude than the first supply voltage that the first supply voltage minus the negative power supply voltage is less than the breakdown voltage.