Patent ID: 7944302

Claim:
An audio sound system, comprising: an audio amplifier including first and second amplifiers coupled to receive an audio signal and adapted to amplify the audio signal, the audio amplifier further including, a measurement block coupled to the first and second amplifiers and adapted to provide first and second conduction signals that are indicative of a conductive state of the first and second amplifiers; a first summation block coupled to receive the first and second conduction signals and adapted to add the first and second conduction signals to generate a sum term; a first difference block coupled to receive the first and second conduction signals and adapted to subtract the second conduction signal from the first conduction signal to generate a difference term; a second summation block coupled to receive the sum and difference terms and adapted to add a portion of the sum term to an average of the difference term to calculate a magnitude of a first bias current signal conducted by the first amplifier; and a second difference block coupled to receive the sum and difference terms and adapted to subtract the average of the difference term from the portion of the sum term to calculate a magnitude of a second bias current signal conducted by the second amplifier; and a speaker coupled to the first and second amplifiers and adapted to convert the amplified audio signal to audible sounds.