hello. I would like to measure the volume(or sensivity) of sound coming into a digital mems mic using ST's Audio IC. Is there any audio ic that can measure the volume (sensitivity) of the sound entering the mic among st products?

[DSEO]

i find a chip STA321MP now!

Is there any reference c-codes that I can refer to?

[Eleon BORLINI]

Hi @DSEO​ ,

the STA321MP audio amplifier is a good solution, but please note that the code available online uses the STM32 X-NUCLEO platforms for developing projects with MEMS microphones: the reference firmware function pack is X-CUBE-MEMSMIC1, and especially the function in \Middlewares\ST\STM32_Audio\Addons\SMR. This library is called Sound Meter, and is an optimized software implementation which embeds a pre-filter which can be configured with different filter types (A and C weighting, DC removal). It has also a smoothing filter which can be configured with any time constant value.

Please let me know if this solution can help your application development.

-Eleon

[DSEO]

I had to unzip the file. (en.X-CUBE-MEMSMIC1.zip)

but SMR folder is not exist. (\Middlewares\ST\STM32_Audio\Addons\SMR )

it has only PDM floder

[Eleon BORLINI]

Hi @DSEO​ ,

maybe something has changed in the last function pack version... you can however find the same directory in the standard X-CUBE-MEMS1 firmware package, folder \Middlewares\ST\STM32_Audio\Addons\SMR.

You can find the application that uses this library in \Projects\STM32L476RG-Nucleo\Applications\IKS02A1\SoundMeter. This is platform dependent, based on STM32L476RG-Nucleo board (but you can use other Nucleo motherboards), and on X-NUCLEO-IKS02A1, that is equipped by theST IMP34DT05 MEMS digital microphone.

Let me please know if you succeed in using it in your code.

-Eleon