Audio Signal Amplifier for Karaoke Player

• US 20110150244A1
• Filed: 04/18/2008
• Published: 06/23/2011
• Est. Priority Date: 04/18/2008
• Status: Active Grant

• Current Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Original Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Inventors: Zhong, Qun, Guan, Hong, Lin, Gaile
• Granted Patent: US 8,335,327 B2
• Time in Patent Office: Days
• US Class Current: 381/120
• CPC Class Codes: H03G 1/0082 using bipolar transistor-type devices

Abstract

A configurable amplifier circuit for a karaoke player is described. In one embodiment, a karaoke player includes: a DVD/CD reader port for coupling to a DVD/CD reader, a microphone input to receive audio signals from an external microphone, an MPEG decoder coupled to the DVD/CD reader port and the microphone input, the MPEG decoder having first and second output terminals, a processor coupled to the MPEG decoder, the processor to control the MPEG decoder, and a configurable amplifier coupled to the first and second output terminals, wherein a first audio signal originating from the first output terminal is selectively amplified by the configurable amplifier circuit in accordance with a second signal originating from the second output terminal.

Claims

1. An apparatus, comprising:

a DVD/CD reader port for coupling to a DVD/CD reader;

a microphone input to receive audio signals from an external microphone;

an MPEG decoder coupled to the DVD/CD reader port and the microphone input, the MPEG decoder having first and second output terminals;

a processor coupled to the MPEG decoder, the processor to control the MPEG decoder; and

a configurable amplifier coupled to the first and second output terminals of the MPEG decoder, wherein a first audio signal originating from the first output terminal is selectively amplified by the configurable amplifier circuit in accordance with a second signal originating from the second output terminal.

2. The apparatus of claim 1 wherein the second signal has a state that is controlled by presence and absence of the external microphone.

3. The apparatus of claim 1 wherein the configurable amplifier circuit further comprises an adjustable gain amplifier stage controlled by the second signal and a fixed gain amplifier stage.

4. The apparatus of claim 3 wherein the adjustable gain amplifier stage is in series with the fixed gain amplifier stage.

5. The apparatus of claim 3 wherein the external microphone, DVD/CD reader, the MPEG decoder, the processor, and the configurable amplifier are components of a karaoke player.

6. The apparatus of claim 5 wherein the selectable gain stage is set to a gain of more than one when the karaoke player is in karaoke mode.

7. The apparatus of claim 5 wherein the selectable gain stage is set to a gain of one when the karaoke player is in DVD or CD mode without receiving audio signals from the external microphone.

8. The apparatus of claim 3 wherein the selectable gain stage is set to a gain of more than one when the microphone input is receiving audio signals from the external microphone.

9. The apparatus of claim 3 wherein when the first signal is originated from a single source, the second signal has a value corresponding to a first mode and an amplified output of the configurable amplifier circuit has a signal to noise ratio meeting a predefined Dolby signal-to-noise requirement.

10. The apparatus of claim 3 wherein when the first signal is originated from multiple sources that include the external microphone, the second signal has a value corresponding to a second mode and an amplified output of the configurable amplifier circuit has a signal to noise ratio that fails a predefined Dolby signal-to-noise requirement.

11. The apparatus of claim 3 where the processor controls a mode of operation of the MPEG decoder and the mode of operation of the MPEG decoder controls a gain of the adjustable gain amplifier stage.

12. The apparatus of claim 11 wherein the processor configures the second signal into a first value corresponding to a first mode of operation and configures the second signal into a second value corresponding to a second mode of operation so as to selectively control the gain of the adjustable gain amplifier stage.

13. The apparatus of claim 11, wherein the processor includes circuitry to reduce a contribution to the first signal from a first source in response to an event.

14. The apparatus of claim 1 wherein the MPEG decoder further includes an internal direct digital amplification (DDX) audio digital to analog converter (DAC) having an output coupled to the first output terminal of the MPEG decoder.

15. The apparatus of claim 1 wherein the second signal is a logic signal that controls a portion of the configurable amplifier circuit.

16. The apparatus of claim 1 wherein the second signal is an analog signal same as the first signal in a first mode of operation.

17. A method to amplify an output of an apparatus, comprising:

in a first mode of operation;

providing a first signal to a configurable amplifier circuit, including decoding information received from a DVD or CD reader to produce a first audio signal, the first signal including the first audio signal;

configuring the configurable amplifier circuit in accordance with a second signal, the second signal having a value corresponding to the first mode of operation;

using a programmed processor, controlling an MPEG decoder to perform the decoding; and

amplifying the first signal with the configurable amplifier circuit to produce an output signal; and

in a second mode of operation, while a microphone is coupled to a microphone input;

providing a third signal to a configurable amplifier circuit, including decoding information received from the DVD or CD reader to produce the first audio signal and receiving an output from the microphone unit comprising a second audio signal, the third signal including a combination of the first audio signal and the second audio signal;

configuring the configurable amplifier circuit in accordance with the second signal, the second signal having a value corresponding to the second mode of operation;

using the programmed processor, controlling the MPEG decoder to perform the decoding; and

amplifying the third signal with the configurable amplifier circuit to produce the output signal.

18. The method of claim 17 wherein the configurable amplifier circuit further comprises an adjustable gain stage controlled by the second output and a fixed gain amplifier stage.

19. The method of claim 18 wherein the adjustable gain stage is in series with the fixed gain amplifier stage.

20. The method of claim 18 further comprising setting the second signal to a logic zero value in the first mode of operation and to a logic one value in the second mode of operation.

21. The method of claim 17 further comprising:

in the second mode of operation, while the microphone is coupled to the microphone input, reducing the first audio signal by pre-determined factor.

22. The method of claim 17 further comprising:

in the second mode of operation, while the microphone is coupled to the microphone input, configuring the second signal to be same as the third signal.

23. The method of claim 17 further comprising configuring the second signal in accordance with instructions from the programmed processor.

24. The method of claim 17 wherein the first mode of operation is an audio listening mode and the second mode of operation is a karaoke mode.

25. A computer readable storage medium storing one or more programs configured for execution by a computer system, the one or more programs comprising instructions for:

in a first mode of operation;

providing a first signal to a configurable amplifier circuit, including decoding information received from a DVD or CD reader to produce a first audio signal, the first signal including the first audio signal;

configuring the configurable amplifier circuit in accordance with a second signal, the second signal having a value corresponding to the first mode of operation;

using a programmed processor, controlling an MPEG decoder to perform the decoding; and

amplifying the first signal with the configurable amplifier circuit to produce an output signal; and

in a second mode of operation, while a microphone is coupled to a microphone input;

providing a third signal to a configurable amplifier circuit, including decoding information received from the DVD or CD reader to produce the first audio signal and receiving an output from the microphone unit comprising a second audio signal, the third signal including a combination of the first audio signal and the second audio signal;

configuring the configurable amplifier circuit in accordance with the second signal, the second signal having a value corresponding to the second mode of operation;

using the programmed processor, controlling the MPEG decoder to perform the decoding; and

amplifying the third signal with the configurable amplifier circuit to produce the output signal.

26. The computer storage medium of claim 25 wherein the configurable amplifier circuit further comprises an adjustable gain stage controlled by the second output and a fixed gain amplifier stage.

27. The computer storage medium of claim 25 wherein the adjustable gain stage is in series with the fixed gain amplifier stage.

28. The computer storage medium of claim 25 further comprising:

in the second mode of operation, while the microphone is coupled to the microphone input, reducing the first audio signal by pre-determined factor.

29. The computer storage medium of claim 25 further comprising:

in the second mode of operation, while the microphone is coupled to the microphone input, configuring the second signal to be same as the third signal.