Reading from 8 or more MEMS PDM Microphones

[Otull.1]

Any advice on which STM32 MCU you'd recommend for capturing the most amount of microphones?

[Eleon BORLINI]

Hi @Otull.1​ , considering the I2S as the most indicated interface (also) for digital MEMS microphone PDM acquisition, I can see that the STM32F411xx MCU family is equipped with 5x I2S muxed interfaces, so you should in principle be able to connect 2x5 microphones (in stereo configuration), maybe not at full mic clock speed however (e.g. 1.024MHz rather than 3.072MHz). I suggest you to start from the existing reference platforms such as the 32F411EDISCOVERY, where the interface code for n.1 digital microphone is already available, or from the audio project in STM32Cube_FW_F4_V1.24.0\Projects\STM32F411E-Discovery\Applications\Audio\Audio_playback_and_record folder.

Btw, to have a more complete panoramic on multiple digital microphone connections, both to take inspiration from the system layout and from the already existing libraries (for active noise cancellation, beamforming, etc...), I suggest the STEVAL-BCNKT01V1 (BlueCoin) platform, which combines 4 digital microphones in stereo mode.

Regards

[Otull.1]

Thanks @Eleon BORLINI​  that sounds like a great starting point.