Improving response of a MEMS capacitive microphone filtering shock noise

This paper deals with the effects of mechanical shock loads on the stability and dynamic response of a MEMS circular capacitive microphone. As results demonstrate, mechanical shock loads affect the dynamic response and the stability region of the capacitive microphone. The results show that the mechanical shock loads can induce considerable noise in the response of the microphone. Therefore, noise filtering is an important issue to eliminate the output response distortions. To achieve this aim we propose a structure for the capacitive microphone with an electrical circuit in order to eliminate the shock noise. In addition the effect of a delay in shock application is also studied, and it is illustrated that a delay in shock application plays an important role in the stability of the capacitive microphone.