Patent ID: 8705771

Claim:
An apparatus for audio amplification, operable with at least one Line-In device, comprising: an audio amplifier circuit configured to receive an audio signal and output an amplified audio signal at an output, the audio amplifier circuit operable in: an on mode in which the received audio signal is amplified and the amplified audio signal is output, and a shutdown mode in which at least some circuitry associated with amplification and outputting an amplified audio signal is disabled; a charge pump circuit for generating the negative voltage supply based on a positive voltage supply; a first diode coupled between the output of the audio amplifier circuit and the positive voltage supply, and a second diode coupled between the output of the audio amplifier circuit and the negative voltage supply; and a control circuit that is arranged to separately control (i) the on and shutdown modes of operation for the audio amplifier circuit, and (ii) the charge pump circuit; wherein the control circuit is operative to concurrently enable the operation of the charge pump circuit to generate the negative voltage supply and enable operation of the audio amplifier circuit in the shut down mode, thereby enabling the audio amplifier circuit, in the shutdown mode, to present to Line-In audio signals from the at least one Line-In device coupled to the output of the audio amplifier circuit a dynamic range between the positive and negative voltages as in the on mode.