Patent ID: 9225301
Filing Date: 2015-12-29
Classification: H03F

Abstract:
1. An audio amplifier apparatus comprising: an audio speaker including a first input and a second input; an audio amplifier configured to receive a single audio signal and produce a plus phase audio signal and a minus phase audio signal, each of the plus phase audio signal and the minus phase audio signal being dependent upon the single audio signal, the plus phase audio signal being received by the first input of the speaker and the minus phase audio signal being received by the second input of the speaker; a current sensing circuit configured to: an amplifying circuit configured to receive the current sensing signal, amplify the current sensing signal, and thereby produce an amplified current sensing signal; and a mixer circuit configured to receive the amplified current sensing signal and an audio drive signal and produce the single audio signal dependent upon the amplified current sensing signal and the audio drive signal, the mixer circuit including two resistors configured as a voltage divider, the single audio signal being produced at a node in-between the two resistors.