MEMSmicrofoons

MEMS microphones are miniature sound transducers manufactured using micro-electromechanical systems technology. Built on silicon, they pair a movable diaphragm with a fixed backplate to form a capacitive sensor and typically integrate amplification, and sometimes analog-to-digital conversion, within a single package. They are widely used in mobile devices, laptops, wearables, automotive systems, and voice-activated equipment because of their small size, robustness, and compatibility with digital processing.

In operation, sound pressure deflects the diaphragm, causing a change in capacitance that is converted to an electrical signal by an on-chip or in-package circuit. Analog MEMS microphones provide a voltage output, while digital MEMS microphones output data streams such as pulse-density modulation (PDM) or I2S/PCM. MEMS devices come in various form factors and port geometries, most commonly bottom-port or top-port, which describe where the acoustic access is located relative to the silicon die.

MEMS microphones can be classified by their output interface rather than their physical form alone. Analog MEMS mics require an external analog-to-digital conversion stage, whereas digital MEMS mics include a digital interface and often an integrated ADC. They are frequently deployed in arrays to enable beamforming, noise suppression, and improved voice capture in noisy environments.

Key performance metrics include sensitivity, signal-to-noise ratio, dynamic range, and total harmonic distortion. Packaging and protection are important, with wafer-level packaging and moisture barriers common. Major manufacturers include Knowles, STMicroelectronics, Infineon, AAC Technologies, and Bosch. MEMS microphones are supported by automotive and consumer electronics standards and broad industry adoption.