Array of PDM microphones best bus interface

[frnt]

Hello,

I would like to design a microphone array with up to 16 microphones. I want to use the stm32h7a3zi board which has a lot of peripherals.

I was looking at the DFSDM interface, but with only 8 channels / 8 filters up to 8 pdm microphones can be handled.

On the contrary, the SAI interface seems to be more promising. If I understood correctly, the SAI interface can be configured as PDM interface, and every SAI can handle up to 6 microphones. Moreover, the SAI interface supports synchronization between SAIs modules. 

Do you have suggestion/comments? 

[Matthew_]

Hello, I know it has been 2 years since you posted this. But, by any chance, were you able to complete the project with SAI interface? I want to create a similar pdm arrary with less microphones.