Combining an audio power amplifier and a power converter in a single device

• US 20090116663A1
• Filed: 11/05/2007
• Published: 05/07/2009
• Est. Priority Date: 11/05/2007
• Status: Active Grant

• Current Assignee: Jawbone Innovations, LLC
• Original Assignee: AliphCom, Inc. (AliphCom Corp.)
• Inventors: Buuck, David C.
• Granted Patent: US 9,036,835 B2
• Time in Patent Office: Days
• US Class Current: 381/94.800
• CPC Class Codes: H03F 2200/03 the amplifier being designed for audio applications
• CPC Class Codes: H03F 3/217 Class D power amplifiers; Switching amplifiers

Abstract

An apparatus is described that includes an audio power amplifier having an input and an output. An alternating-current to direct-current power converter is coupled to the audio power amplifier in a single package to supply power to the audio power amplifier.

Claims

1. An apparatus comprising:

an audio power amplifier having an input and an output; and

an alternating-current to direct-current power converter coupled to the audio power amplifier in a single package to supply power to the audio power amplifier.

2. The apparatus of claim 1, wherein the audio power amplifier and power converter reside on a single substrate of an integrated circuit.

3. The apparatus of claim 1, wherein the audio power amplifier and power converter reside on respective separate substrates within the package.

4. The apparatus of claim 1, further comprising control circuitry coupled to the audio power amplifier and said alternating-current to direct-current power converter, wherein the control circuitry resides within the single package.

5. The apparatus of claim 4, wherein the control circuitry adjusts operating characteristics of the power converter responsive to a signal provided as an input to the audio power amplifier.

6. The apparatus of claim 4, further comprising a limiter coupled to the audio power amplifier and the control circuitry to limit a signal provided as an input to audio power amplifier responsive to a control signal from the control circuitry, wherein the limiter resides within the single package.

7. The apparatus of claim 1, wherein the alternating-current to direct-current power converter is a switching-mode power supply.

8. The apparatus of claim 7, wherein said audio power amplifier is a class D audio amplifier.

9. An integrated circuit comprising:

an audio power amplifier;

a power converter to supply said audio power amplifier with a direct-current power source; and

control circuitry coupled to the audio power amplifier and the power converter to monitor an output of the power converter and to adjust an operating characteristic of the power converter responsive to the output of said power converter.

10. The integrated circuit of claim 9, wherein the power converter is a switched-mode power supply.

11. The integrated circuit of claim 10, wherein the control circuitry monitors the output of the power converter for voltage droop and adjusts a duty cycle of said power converter responsive to the voltage droop.

12. The integrated circuit of claim 10, wherein the audio power amplifier is a class D audio power amplifier.

13. The integrated circuit of claim 9, wherein the control circuitry modifies an input signal of the audio power amplifier responsive to detection of distortion of an output signal of the audio power amplifier.

14. The integrated circuit of claim 9, further comprising a limiter that restricts a signal level of an input to the audio power amplifier responsive to the control circuitry.

15. An audio system comprising:

an integrated circuit having a first audio power amplifier, a power converter to provide power to the first audio power amplifier, and control circuitry to modify an operating characteristic of the power converter responsive to an operating condition of the first audio power amplifier; and

a speaker coupled with the integrated circuit to reproduce an audio signal amplified by the first audio power amplifier.

16. The audio system of claim 15, wherein the integrated circuit includes a second audio power amplifier powered by the power converter.

17. The audio system of claim 16, wherein the control circuitry includes a limiter to restrict a signal level of a first input signal into the first audio power amplifier and a second input signal into the second audio power amplifier.

18. The audio system of claim 17, wherein the level of the first input signal and the second input signal restricted by the limiter is programmable.

19. The audio system of claim 17, wherein the control circuitry adjusts the level of the first input signal and the second input signal responsive to an input power signal for the power converter.

20. The audio system of claim 17, wherein the limiter are implemented using a digital signal processor.

21. The audio system of claim 15, wherein the control circuitry modifies a duty cycle of the power converter responsive to an input signal to the first audio power amplifier.

22. The audio system of claim 16, wherein the audio power amplifier is a class D audio amplifier.