Is it possible to run selftest for stereo PDM microphones connected to STM32 via I2S?

AMukh.3 · ‎2023-02-07

AMukh.3 · ‎2023-02-07

I'm running the project on STM32F412 using PDM2PCM library and I want to know if there any methods, libs or technologies that allow to run "on device" firmware self test for two PDM IMP34DT05 microphones connected using i2s peripheral.

Device has no additional speakers to generate sound signal.

Eleon BORLINI · ‎2023-02-14

Hi @AMukh.3 ,

For the microphone a self test like the one on accelerometers or IMUs is not available.

And it is not so easy to check the integrity of a microphone without an acoustical stimulus, like a speaker or a generic sinewave tone.

However, you might try by acquiring the mic signal and check the integral noise (A-weighted, 20Hz-20kHz filtered) in a silent ambient: for a digital microphone like MP23DB01HP, it should be around -105dBFS(A), or 30 dBSPL.

-Eleon