MEMS measurement microphone compatible to P48 amplifiers

Abstract

In recent years, micro-electromechanical systems (MEMS) microphones have become increasingly popular in consumer-grade products due to their affordability, performance and low manufacturing variability. This paper presents a pre-amplifier designed to interface with these MEMS capsules and IEC 61938 pro-audio devices, offering high-precision audio measurement and recording at a low cost. The design allows the pre-amplifier and capsule to fit into a ¹/₂-inch or 12 mm housing, making it a drop-in replacement for commercial measurement microphones. Comprehensive calculations, simulations and measurements of the pre-amplifier demonstrate its excellent performance. Testing of the device, when paired with a commercially available MEMS capsule, in an acoustically treated chamber, further validates its capabilities. The detailed circuit description also facilitates easy adaptation of the pre-amplifier to other MEMS capsules.