Patent ID: 8922278

Claim:
An audio power amplifier comprising: a four-quadrant power supply having a synchronous output rectifier; a first amplification unit and a second amplification unit, each amplification unit comprising: a switching voltage amplifier having a command signal input and an amplified signal output, an output filter between the amplified signal output and a load terminal, a current compensator with a current-compensated command signal output coupled to the command signal input of the switching voltage amplifier, an inner current feedback loop feeding a measurement of current measured at the output filter back to a summing input of the current compensator, a voltage compensator with a voltage-compensated command signal output coupled to the summing input of the current compensator, and an outer voltage feedback loop feeding voltage at the load terminal back to a summing input of the voltage compensator; and control electronics providing signal inputs to the first and second amplification units and controlling the first and second amplification units such that the first and second amplification units are operable with separate loads, in parallel driving a common load, or across a bridge-tied-load.