Battery charger, including an amplifier for audio signals, for portable audio devices

Abstract

A battery charger is used for charging a battery incorporated in a portable audio device such as a portable telephone, and it comprises a connector and a circuit block for performing charging operation with the battery of the portable audio device via the connector. The circuit block contains a digital power amplifier that ensures digitization of audio signals transmitted thereto from the portable audio device via the connector. The battery charger can be connected with speakers, which produce sounds based on digital audio signals amplified by the digital power amplifier. Since the digital power amplifier has a good efficiency in power consumption and produces a very small amount of heat during operation, the battery charger can be considerably downsized, and it can reliably ensure a high quality reproduction of audio signals during charging operation for the battery of the portable audio device in progress.

Dependencies are inferred from the claim text.