Granted Patent B2

US 7,930,046 · App. 11/365,231 · Granted Apr 19, 2011

Abstract

Claims (95)

1. A codec comprising:

an output module for converting a digital input signal into an analog output signal;

a control interface, operatively coupled to the controller module, for receiving a rules enable signal and for selectively enabling or disabling selected ones of a plurality of disconnect rules in response to the rules enable signal, the plurality of disconnect rules comprising a first disconnect rule;

a controller module, operatively coupled to the output module, for monitoring a plurality of status conditions and to:

when the first disconnect rule is enabled, setting an output mute switch to mute an audio output in response to determining that the first condition is met;

when the first disconnect rule is enabled, setting the output mute switch such that the audio output is not muted in response to determining that the first condition is not met; and

when the first disconnect rule is disabled, setting the output mute switch such that the audio output is not muted both when the first condition is met and when the first condition is not met.

2. The codec of claim 1 wherein:

the control interface further is for receiving an external mute signal that can be asserted or deasserted;

wherein the first condition is based on the external mute signal, and wherein the first disconnect rule includes assert the mute signal when the external mute signal is asserted.

3. The codec of claim 1 wherein:

the control interface further is for receiving a reset signal that can be asserted or deasserted;

wherein the first condition is based on the reset signal, and wherein the first disconnect rule includes assert the mute signal when the reset signal is asserted.

4. The codec of claim 1 further comprising:

a multiplexer module for switching a source of the digital input signal from a first input signal to a second input signal;

wherein the first condition is based on the source of the digital input signal, and wherein the first disconnect rule includes assert the mute signal when the source of the digital input signal is switched.

5. The codec of claim 1 wherein the digital input signal includes an input format, wherein the first condition is based on the input format, and wherein the first disconnect rule includes assert the mute signal when the input format is changed.

6. The codec of claim 1 wherein the output module generates a lock signal that is asserted when the output module is locked on the digital input signal and is deasserted when the output module loses lock on the digital input signal, wherein the first condition is based on the lock signal, and wherein the first disconnect rule includes assert the mute signal when the lock signal is deasserted.

7. The codec of claim 1 wherein the output module includes a digital to analog converter having an analog portion that is powered by a power source having an analog power level, wherein the first condition is based on the analog power level, and wherein the first disconnect rule includes assert the mute signal when the analog power level compares unfavorably to an analog power level threshold.

8. The codec of claim 1 wherein the output module includes a digital to analog converter having a digital portion that is powered by a power source having a digital power level, wherein the first condition is based on the digital power level, and wherein the first disconnect rule includes assert the mute signal when the digital power level compares unfavorably to a digital power level threshold.

9. The codec of claim 1 further comprising:

an amplifier module, operatively coupled to the output module, for producing an amplified output signal for an audio output device from the analog output signal;

wherein the output mute switch disconnects the amplified output signal from the audio output device when the mute signal is asserted.

10. The codec of claim 1 wherein the digital input signal is one of: an audio signal, and a video signal.

11. The codec of claim 1 wherein the output mute switch may further be engaged by an external processing module.

12. The codec of claim 1 wherein the first condition is received from an external device.

13. The codec of claim 1 wherein the mute signal includes a plurality of individual mute signals and the output mute switch includes a plurality of mute devices and wherein the plurality of individual mute signals are asserted in response to the first disconnect rule.

14. The codec of claim 1 wherein the mute signal includes a plurality of individual mute signals and the output mute switch includes a plurality of mute devices and wherein only one of individual mute signals are asserted in response to the first disconnect rule.

15. A codec integrated circuit comprising:

an output module for converting a digital input signal into an analog output signal;

an output pad for coupling a mute signal to an output mute switch that is external to the codec integrated circuit;

a control interface, operatively coupled to the controller module, for receiving a rules enable signal; and

a controller module, operatively coupled to the output module and the output pad, for monitoring a plurality of status conditions including a first condition, for selectively enabling or disabling selected ones of a plurality of disconnect rules in response to the rules enable signal, the plurality of disconnect rules comprising a first disconnect rule, the controller module to:

when the first disconnect rule is enabled, setting an output mute switch to mute an audio output in response to determining that the first condition is met;

when the first disconnect rule is enabled, setting the output mute switch such that the audio output is not muted in response to determining that the first condition is not met; and

when the first disconnect rule is disabled, setting the output mute switch such that the audio output is not muted both when the first condition is met and when the first condition is not met.

16. The codec integrated circuit of claim 15 wherein:

the control interface further is for receiving an external mute signal that can be asserted or deasserted;

wherein the first condition includes the external mute signal, and wherein the first disconnect rule includes assert the mute signal when the external mute signal is asserted.

17. The codec integrated circuit of claim 15 wherein:

the control interface further is for receiving a reset signal that can be asserted or deasserted;

wherein the first condition includes the reset signal, and the first disconnect rule includes assert the mute signal when the reset signal is asserted.

18. The codec integrated circuit of claim 15 further comprising:

a multiplexer module for switching a source of the digital input signal from a first input signal to a second input signal;

wherein the first condition includes the source of the digital input signal, and wherein the first disconnect rule includes assert the mute signal when the source of the digital input signal is switched.

19. The codec integrated circuit of claim 15 wherein the digital input signal includes an input format, wherein the first condition includes the input format, and wherein the first disconnect rule includes assert the mute signal when the input format is changed.

20. The codec integrated circuit of claim 15 wherein the output module generates a lock signal having a lock signal that is asserted when the output module is locked on the digital input signal and is deasserted when the output module loses lock on the digital input signal, wherein the first condition includes the lock signal, and wherein the first disconnect rule includes assert the mute signal when the lock signal is deasserted.

21. The codec integrated circuit of claim 15 wherein the output module includes a digital to analog converter having an analog portion that is powered by a power source having an analog power level, wherein the first condition includes the analog power level, and wherein the first disconnect rule includes assert the mute signal when the analog power level compares unfavorably to an analog power level threshold.

22. The codec integrated circuit of claim 15 wherein the output module includes a digital to analog converter having a digital portion that is powered by a power source having a digital power level, wherein the first condition includes the digital power level, and wherein the first disconnect rule includes assert the mute signal when the digital power level compares unfavorably to a digital power level threshold.

23. The codec integrated circuit of claim 15 further comprising:

an amplifier module, operatively coupled to the output module, for producing an amplified output signal for an audio output device from the analog output signal;

wherein the output mute switch disconnects the amplified output signal from the audio output device when the mute signal is asserted.

24. The codec integrated circuit of claim 15 wherein the digital input signal is one of:

an audio signal, and a video signal.

25. The codec integrated circuit of claim 15 wherein the the first condition is received from an external device.

26. The codec integrated circuit of claim 15 wherein the mute signal includes a plurality of individual mute signals and the output mute switch includes a plurality of mute devices and wherein the plurality of individual mute signals are asserted in response to at least one of the plurality of disconnect rules.

27. The codec integrated circuit of claim 15 wherein the mute signal includes a plurality of individual mute signals and the output mute switch includes a plurality of mute devices and wherein only one of individual mute signals are asserted in response to at least one of the plurality of disconnect rules.

28. A method comprising:

converting a digital input signal into an analog output signal;

monitoring a plurality of status conditions in a codec, the plurality of status conditions comprising a first condition;

receiving a rules enable signal;

selectively enabling or disabling selected ones of a plurality of disconnect rules in response to the rules enable signal, the plurality of disconnect rules comprising a first disconnect rule;

when the first disconnect rule is enabled, setting an output mute switch to mute an audio output in response to determining that the first condition is met;

when the first disconnect rule is enabled, setting the output mute switch such that the audio output is not muted in response to determining that the first condition is not met; and

when the first disconnect rule is disabled, setting the output mute switch such that the audio output is not muted both when the first condition is met and when the first condition is not met.

29. The method of claim 28 wherein the first condition is based on an external mute signal.

30. The method of claim 28 wherein the first condition is based on a reset signal.

31. The method of claim 28 further comprising:

wherein the first condition is based on switching a source of a digital input signal.

32. The method of claim 28 wherein the digital input signal includes an input format and the first condition is based on a change in the input format.

33. The method of claim 28 wherein the first condition is based on losing a lock between the digital input signal and the analog output signal.

34. The method of claim 28 wherein the first condition is based on the relationship between a threshold and an analog power level of an analog portion of an analog to digital converter.

35. The method of claim 28 wherein the first condition is based on the relationship between a threshold and an digital power level of a digital portion of an analog to digital converter.

36. The method of claim 28 further comprising:

generating an amplified output signal for an audio output device from the analog output signal; and

disconnecting the amplified output signal from the audio output device when the mute signal is asserted.

37. The method of claim 28 wherein the digital input signal is one of: an audio signal, and a video signal.

38. The method of claim 28 wherein the plurality of conditions includes at least one condition received from an external device and at least one condition generated internally.

39. The method of claim 28 wherein the mute signal includes a plurality of individual mute signals and output mute switch includes a plurality of mute devices and wherein the plurality of individual mute signals are asserted in response to at least one of the plurality of disconnect rules.

40. The method of claim 28 wherein the mute signal includes a plurality of individual mute signals and output mute switch includes a plurality of mute devices and wherein only one of individual mute signals are asserted in response to at least one of the plurality of disconnect rules.

41. A codec integrated circuit comprising:

an output module for converting a digital input signal into an analog output signal;

an input pad for receiving a rules enable signal;

a controller module, operatively coupled to the output module and the input pad, for selectively enabling or disabling selected ones of a plurality of disconnect rules based on the rules enable signal, and for asserting a mute signal for engaging an output mute device based on enabled ones of the plurality of disconnect rules and a plurality of conditions comprising a first condition, the plurality of disconnect rules comprising a first disconnect rule, the controller module to:

when the first disconnect rule is enabled, setting an output mute switch to mute an audio output in response to determining that the first condition is met;

when the first disconnect rule is enabled, setting the output mute switch such that the audio output is not muted in response to determining that the first condition is not met; and

when the first disconnect rule is disabled, setting the output mute switch such that the audio output is not muted both when the first condition is met and when the first condition is not met.

42. A codec comprising:

an output module for converting a digital input signal into an analog output signal;

a controller module, operatively coupled to the output module, for monitoring a plurality of status conditions comprising a first condition and for asserting a mute signal for engaging an output mute switch based on a plurality of disconnect rules comprising a first disconnect rule, the controller module to:

when the first disconnect rule is enabled, setting an output mute switch to mute an audio output in response to determining that the first condition is met;

when the first disconnect rule is enabled, setting the output mute switch such that the audio output is not muted in response to determining that the first condition is not met; and

when the first disconnect rule is disabled, setting the output mute switch such that the audio output is not muted both when the first condition is met and when the first condition is not met; and

a multiplexer module for switching a source of the digital input signal from a first input signal to a second input signal;

wherein one of the plurality of status conditions includes the source of the digital input signal, and wherein one of the plurality of disconnect rules includes assert the mute signal when the source of the digital input signal is switched.

Assignments (16)