Audio amplifier circuit and method of operation thereof

摘要

The present invention concerns an audio amplifier circuit (1) designed to provide an output signal (Vout) to an audio transducer (2), said audio amplifier circuit (1) comprising an audio power amplifier (3) designed to receive an audio signal (Sin) at its input and designed to generate said output signal (Vout) at its output, a sensor (4) designed to detect an audible sound having at least one noise component, to generate a detected signal (Sdet) at its output.
It further comprises a processing block (5) which is designed to receive said detected signal (Sdet) at its input and to generate an off signal (Soff) at its output, the latter being located at the input of said audio power amplifier (3), said processing block (5) processing said detected signal (Sdet) according to said input signal (Sin) to identify said noise component (Vn) of said detected signal (Sdet) to generate a reference signal (Smod'), said processing block (5) generating said off signal (Soft) at its output when the value of said input signal (Sin) is lower than the value of said reference signal (Smod').