Modeling and simulation of a condenser microphone

A nodal analysis model of a condenser microphone has been implemented in an IC design environment. The fundamental characteristics, including sensitivity, frequency response and output referred noise are obtained by co-simulation with the microphone and the readout circuit using Cadence/Spectre® simulator. The new model is capable of dealing with the multi-field coupling effects including acoustical, mechanical and electrostatic behavior. Both the numerical analysis and measured data agree with the nodal simulation results. In addition, the implemented readout circuit shows good performance of interfacing a condenser microphone with 63 dB SNR and −35 dBV/Pa sensitivity. Co-simulating the microphone and readout circuit, enables trade-off analysis between the acoustical-electro-mechanical and electronic design parameters.