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 ...

Deciding to go for a full digital design for the circuitry, the peripheral is based off of a MEMS microphone ... the PCM samples from the microphone’s I²S interface into a format better suited ...

Knowles of the U.S. in 2013 was the biggest supplier of packaged MEMS microphones ready for assembly on printed circuit boards, according to IHS Technology. Germany’s Infineon, meanwhile, was the ...