主权项 |
1. An audio signal processing circuit, comprising:
first, second, third, and fourth terminals for coupling to a headset having a first and a second speakers, a microphone, and a headset ground, wherein the first and the second terminals are configured for providing a first and a second audio signals to the first and the second speakers, respectively, wherein the third and the fourth terminals are configured to be either a microphone connection terminal or a headset ground connection terminal, respectively, depending on the type of the headset; an audio jack detection circuit configured to detect the headset ground connection terminal and to provide a corresponding headset ground selection signal; first and second audio amplifiers for providing the first and the second audio signals to the first and second terminals, respectively; an audio amplifier reference node coupled to inputs of the first and the second audio amplifiers for providing a common mode signal; a first switch device responsive to the headset ground selection signal and configured to connect the audio amplifier reference node to the detected headset ground connection terminal; a second switch device responsive to the headset ground selection signal and configured to couple the detected headset ground connection terminal to a ground terminal of the audio processing circuit; a third switch device responsive to the headset ground selection signal and configured to couple the microphone connection terminal to a microphone bias circuit; and a fourth switch device responsive to the headset ground selection signal and configured to couple the microphone connection terminal to a push button signal detection circuit. |