The sensing device is a MEMS microphone that outputs a pulse density modulated (PDM) signal. There are chips available to directly interface such a microphone to a USB port, but [Mahesh] found ...

Microphones for measurement purposes can be had for a very large outlay, but here’s [Peter Riccardi] with a unit designed around an array of MEMS capsules ... aspects of its design for those ...

Akustica's AKU2000 Microphone Chip is also the world's only single-chip silicon microphone. The combination of Akustica's expertise in patented CMOS MEMS semiconductor design and X-FAB's device ...