Stereo FMAC

[etheory]

Hi ST!

I am writing to ask if any ST MCU's will be released with 2x independent FMAC units?

At the moment, doing stereo audio processing with a single FMAC is problematic (and ST MCU's ONLY have a single FMAC unit), especially being unable to load the buffers automatically for processing (which would allow switching between two different data streams, which currently isn't possible).

Have any other clients asked for such functionality?

Thanks.

[DavidNaviaux]

With only one FMAC, does that mean I can only have one digital switch mode power supply being controlled by the STM32G4 series MCU?

[etheory]

You have to manually switch between two sets of coefficients manually unfortunately.

It would be better (and faster) to have two separate units for stereo audio, but they don't (because I guess it's built for a single motor controller and not audio).

[DavidNaviaux]

I just returned from an STM32G474 power supply design workshop and it is very possible to implement more than one DSMPS using a single STM32G474.  Yes, only one FMAC means that only one of the power supplies can use it.  But the other power supplies can be implemented by hand coding what the FMAC is doing in an ADC interrupt handler.  It's not as fast but it is not a problem to support two other DSMPSs running at 200kHz switching frequency.  I highly recommend this workshop: https://www.biricha.com/ 

[etheory]

You can use the FMAC on multiple datasets by packing them within the internal FMAC RAM and manually switching the base address of each set of coefficiencts to process the separate streams, but it's not automatic as I think it should be....