Battery charger for portable audio devices

• US 20030042868A1
• Filed: 08/27/2002
• Published: 03/06/2003
• Est. Priority Date: 08/30/2001
• Status: Active Grant

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Muramatsu, Toshihiko
• Granted Patent: US 6,788,026 B2
• Time in Patent Office: Days
• US Class Current: 320/107
• CPC Class Codes: H02J 7/0044 specially adapted for holding portable devices containing batteries H02J7/0045 takes precedence
• CPC Class Codes: H04M 1/6041 Portable telephones adapted for handsfree use

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.

Claims

1. A battery charger for charging a battery incorporated in a portable audio device, comprising:

a connector providing connectibility with the portable audio device; and

a circuit block for performing a charging operation of the battery of the portable audio device via the connector, wherein the circuit block contains a digital power amplifier that ensures digitization of audio signals transmitted thereto from the portable audio device via the connector.

2. A battery charger according to claim 1, wherein the circuit block is capable of reproducing audio signals transmitted thereto from the portable audio device.

3. A battery charger according to claim 1, wherein the digital power amplifier amplifies and outputs digitized audio signals from the portable audio device.

4. A battery charger according to claim 1 further comprising at least one terminal for outputting signals processed in the circuit block.

5. A battery charger according to claim 2 further comprising at least one terminal for outputting signals processed in the circuit block.

6. A battery charger according to claim 3 further comprising at least one terminal for outputting signals processed in the circuit block.

7. A battery charger according to claim 1, wherein a single power source is used for both the charging operation and playback operation of the portable audio device.

8. A battery charger according to claim 2, wherein a single power source is used for both the charging operation and playback operation of the portable audio device.

9. A battery charger according to claim 3, wherein a single power source is used for both the charging operation and playback operation of the portable audio device.

10. A battery charger according to claim 1 further comprising a selector, wherein the connector has a charging terminal for use in the charging operation of the portable audio device as well as a plurality of terminals for use in transmission of signals with respect to the portable audio device, so that the selector is operated to select a desired terminal from among the plurality of terminals of the connector.

11. A battery charger according to claim 2 further comprising a selector, wherein the connector has a charging terminal for use in the charging operation of the portable audio device as well as a plurality of terminals for use in transmission of signals with respect to the portable audio device, so that the selector is operated to select a desired terminal from among the plurality of terminals of the connector.

12. A battery charger according to claim 3 further comprising a selector, wherein the connector has a charging terminal for use in the charging operation of the portable audio device as well as a plurality of terminals for use in transmission of signals with respect to the portable audio device, so that the selector is operated to select a desired terminal from among the plurality of terminals of the connector.

13. An audio system comprising:

a portable audio device;

a battery charger that comprises a connector providing connectibility with the portable audio device, and a circuit block for performing a charging operation with the battery of the portable audio device via the connector, wherein the circuit block contains a digital power amplifier that ensures digitization of audio signals transmitted thereto from the portable audio device via the connector; and

at least one terminal for outputting digital audio signals amplified by the digital power amplifier to a speaker.

14. An audio system according to claim 13, wherein a single power source is used for both the charging operation and playback operation of the portable audio device.

15. An audio system according to claim 13 further comprising a selector, wherein the connector has a charging terminal for use in the charging operation of the portable audio device as well as a plurality of terminals for use in transmission of signals with respect to the portable audio device, so that the selector is operated to select a desired terminal from among the plurality of terminals of the connector.