Table A5.

Lumped parameter model for the acoustic impedance of the MEMS microphone (MEMS MIC) Z_MEMS [kg/s/m⁴], [23].

$Z_{tot,mic\_us}$	Ztot,mic_us: total acoustic impedance of an unsealed MEMS MIC without considering the pressure port and the interaction between the inlet channel and the surroundings (acoustic radiation) [kg/s/m4], calculated based on References [13,25,26]
$Z_{ps,add}$	Zps,add: additional reactive and resistive impedance of the pneumatic system that is independent of the number of protective diaphragms [kg/s/m4], calculated based on Equations (A11)–(A13) with rps,add and lps,add (cf. Figure A1)
$Z_{MEMS}=Z_{tot,mic\_us}+Z_{ps,add}$		(A22)