A 22dBA digital optical MEMS microphone

Optical microphones represent a promising alternative to the conventional capacitive MEMS microphones, especially when aiming at ultra-low noise applications. This paper reports the design and development of a SiP (System-in-Package) digital optical microphone with 71.6dBA SNR in 5×5×2mm ³ package with output sensitivity of -21dBFS/Pa. The system concept is introduced, the design and modeling of the main blocks are presented and the measured results are analyzed.