An optimal design of high performance interface circuit with acoustic transducer model

Reducing interface circuit power consumption without compromising low noise performance is an increasing challenge for portable sensor applications. This paper reports a high power efficiency and high SNR capacitive MEMS microphone interface circuit using a negative feedback amplifier. The transistors in the interface circuit are biased in the deep subthreshold region, for a 45% better Figure of Merit (FoM) that considers both noise and power. The MEMS microphone mechanical behavior is modeled using an analog hardware description language to enable co-simulation of the microphone together with the circuit. This co- simulation platform enables optimization of the MEMS microphone simultaneously with the interface circuit.