Patent ID: 6414549
Filing Date: 2002-07-02
Classification: H03F

Abstract:
An audio amplifier comprising:a voltage feedback amplifier stage having an audio signal input; a push-pull voltage gain/phase splitter stage driven from said voltage feedback amplifier stage; a bias adjustment stage driven from said push-pull voltage gain/phase splitter stage; a current drive stage driven from said bias adjustment stage; an output stage driven from said current drive stage, said output stage comprising a plurality of paralleled current shared individual MOS output transistors driving an output node; an output load having a first terminal connected to said output node and a second terminal connected to a fixed voltage potential; a first voltage feedback loop comprising a voltage feedback stage comprising an operational amplifier, said feedback stage having an input connected to a voltage divider driven from said first terminal of said load and an output connected to a feedback input node in said voltage feedback amplifier stage; a second voltage feedback loop comprising a voltage feedback stage having an input connected to said output node and an output connected to a feedback input node in said push-pull voltage gain/phase splitter stage; and a third feedback loop comprising a current feedback stage having an input in series between said output node and said load and an output connected to a feedback input node in said voltage feedback amplifier stage.