Patent ID: 8005242

Claim:
An alternative sensing circuit for a micro-electro-mechanical system (MEMS) microphone, comprising: an MEMS condenser microphone component; an MEMS electret condenser microphone component; a first switch and a second switch, respectively connected to the MEMS condenser microphone component and the MEMS electret condenser microphone component; a bias component, having a first end connected to the first switch and the second switch; and a third switch and a fourth switch, respectively connected to a second end of the bias component, respectively connected to a voltage source and a ground potential, and selectively forming a first current path or a second current path, wherein when the first switch and the third switch are turned on, the first current path is formed, and the second switch and the fourth switch are turned off, and the first current path allows the MEMS condenser microphone component to obtain a bias from the voltage source through the bias component, such that the MEMS condenser microphone component senses an acoustic wave signal as the output of the sensing circuit for the MEMS microphone, when the second switch and the fourth switch are turned on, the second current path is formed, and the first switch and the third switch are turned off, and the second current path allows outputting the sensing result of the acoustic wave sensed by the MEMS electret condenser microphone component as the output of the sensing circuit for the MEMS microphone.