Apparatus and method for detecting insertion anomaly of an audio jack

1. A method for monitoring and recovering from audio jack connection anomalies of a mobile device, the method comprising:

detecting a state change of a detection terminal of an audio jack detection circuit of the mobile device from a first state to a second state;

applying an oscillating signal to a microphone terminal of the audio jack detection circuit in response to the detected state change using an oscillating signal source of the mobile device;

detecting at logic of detection circuit, a stable state of the detection terminal for a debounce period using the second state and the oscillating signal;

stop applying the oscillating signal to the microphone terminal after detecting the stable state of the detection terminal; and

providing an indication of a connected state of an audio jack connector or a disconnected state of the audio jack connector after detecting the stable state of the detection terminal.

2. The method of claim 1 , wherein if the connected state of the audio jack connector is provided, the method includes:

ramping on a first detection current source of the audio jack detection circuit coupled to the detection terminal of a first audio jack connector;

receiving a reference information at a comparator of the audio jack detection circuit;

receiving a voltage of the detection terminal at the comparator;

providing comparison information at an output of the comparator, the comparison information indicative of a comparison of the voltage of the detection terminal and the reference information; and

wherein a first state of the comparison information indicates an audio jack insertion anomaly is due to moisture at the first audio jack connector.

3. The method of claim 2 , wherein the providing comparison information includes evaluating a plurality of comparison results over a predetermined comparison interval.

4. The method of claim 3 , wherein the evaluating a plurality of comparison results over a predetermined comparison interval includes evaluating more than two comparison results over the predetermined comparison interval.

5. The method of claim 2 , including ramping on a second detection current source of the audio jack detection circuit.

6. The method of claim 3 , including providing second comparison information at an output of the comparator, the second comparison information indicative of a second comparison of the voltage of the detection terminal and second reference information.

7. The method of claim 6 , wherein the providing second comparison information includes evaluating a plurality of second comparison results over a second predetermined comparison interval.

8. The method of claim 7 , wherein the evaluating a plurality of second comparison results over a second predetermined comparison interval includes evaluating more than two second comparison results over the second predetermined comparison interval.

9. The method of claim 7 , wherein if the plurality of second comparison results are consistently at a first level, the method includes providing an output indicative of a full insertion of the first audio jack connector with a second audio jack connector.

10. The method of claim 9 , including disabling a second detection current source of the audio jack detection circuit.

11. The method of claim 7 , wherein if the plurality of second comparison results are not consistently at a first level, the method includes providing an output indicative of a partial insertion of the first audio jack connector with a second audio jack connector.

12. The method of claim 11 , including disabling a second detection current source of the audio jack detection circuit.

13. The method of claim 5 , wherein the ramping on the second detection current source includes ramping the second detection current source simultaneously with ramping the first detection current source.

14. The method of claim 13 , wherein the providing comparison information includes evaluating a plurality of comparison results over a predetermined comparison interval.

15. The method of claim 14 , wherein if the plurality of comparison results are consistently at a first level, the method includes providing an output indicative of no moisture at the first audio jack connector.

16. The method of claim 15 , including disabling the second detection current source.

17. The method of claim 14 , wherein if the plurality of comparison results are not consistently at a first level, the method includes providing an output indicative of moisture at the first audio jack connector.

18. The method of claim 11 , including disabling a second detection current source of the audio jack detection circuit.

19. The method of claim 1 , including resetting a removal debounce counter before applying the oscillating signal; and

wherein the detecting a stable state of the detection terminal includes comparing a current state of the detection terminal to a saved state of the detection terminal;

incrementing the removal debounce counter if the second state equals the saved state;

comparing a value of the removal debounce counter to a threshold; and

indicating the stable state of the detection terminal if the value of the removal debounce counter exceeds the threshold.

20. The method of claim 19 , including resetting the value of the removal debounce counter if the current state does not equal the saved state; and

saving the current state as the saved state.