Environmental effects on the acoustic behavior of a screen-protected MEMS pressure sensor

We investigate the acoustic behavior of a screen-protected MEMS pressure sensor in particle-contaminated environments. An acoustic model of the sensor housing taking into account the number of openings is derived and verified with microphone measurements. It is shown that the real viscous resistance is more than two times higher than theoretically predicted by the Poiseuille flow model. Thus, a realistic resistance is calculated and inserted into the model, which subsequently describes the acoustic characteristics of the pressure sensor in dependence of the degree of plugging correctly.