Investigating the Controllability of Corrugated Piezoelectric MEMS Microphones

Abstract:
We present an investigation on the controllability of a piezoelectric MEMS microphone featuring a fully clamped corrugated membrane in order to realize force-feedback control. The measured electrical frequency response, which does not resemble a typical second-order system response, poses a challenge regarding the stability of the control loop. It is shown that this deviating behaviour can be explained by electrical crosstalk on the MEMS device itself. Two potential solutions are suggested: Re-designing the MEMS transducer to reduce undesired feedthrough effects or changing the control scheme to a self-sensing collocated control approach with guaranteed stability.