nRF5340 PDM frequency range supported?

RE: nRF5340 PDM frequency range supported?

Priyanka — Thu, 01 Aug 2024 05:36:36 GMT

Hi,

Please create a new ticket for your concern so that we can assist you better with the proper experts and this also helps keep Devzone clean and easy to search for future seekers.

-Priyanka

RE: nRF5340 PDM frequency range supported?

ClinicalAudio — Wed, 31 Jul 2024 17:51:20 GMT

Also interested in this - I'm wanting to understand the limits and implementations of higher (than 1.28MHz) clock frqs for PDM

RE: nRF5340 PDM frequency range supported?

Priyanka — Thu, 13 Jun 2024 10:00:32 GMT

Hi Ever,

The confusion has arisen from the product specification. So basically, from the documentation, it is mentioned that one of the main feature of PDM is 16kHz output sample rate:

I guess the equations confused you, or gave the idea that the legacy module is flexible for various frequencies. But it was actually designed for the following two combinations which always gives out 16kHz PCM:

So yes it might work for different combinations, but 16kHz id the one that we have designed, tested, guaranteed and qualified.

Hope this clears things.

Regards,

Priyanka

RE: nRF5340 PDM frequency range supported?

responsible_duck — Thu, 06 Jun 2024 05:07:23 GMT

What about 24 kHz? Seems doable?

RE: nRF5340 PDM frequency range supported?

Priyanka — Wed, 05 Jun 2024 11:56:27 GMT

Hi,

According to the discussion with the experts, it looks like we cannot reliably support the 48kHz.

-Priyanka

RE: nRF5340 PDM frequency range supported?

Priyanka — Thu, 30 May 2024 13:24:55 GMT

Hi,

Sorry for the delay caused. I have raised the issue once again with our internal team. I guess they missed the ticket somehow over large influx of cases during the holidays and vacation that were there. Once again, apologies for the inconvenience and I will keep you updated.

-Priyanka

RE: nRF5340 PDM frequency range supported?

Priyanka — Tue, 02 Apr 2024 13:04:35 GMT

Hi,

I have inquired internally and will get back to you as soon as I hear from them.

-Priyanka

RE: nRF5340 PDM frequency range supported?

responsible_duck — Tue, 26 Mar 2024 14:00:56 GMT

Thanks Priyanka ! Is there a documented range that is supported? Would 24 kHz or 32 kHz be too fast?

RE: nRF5340 PDM frequency range supported?

Priyanka — Tue, 26 Mar 2024 08:53:49 GMT

Hi,

It looks like the required PDM clock frequency of 3.072MHz would be too fast for the "frequency doubler" to function when using APLL source. By setting FDBYPASS=1, it should be doable on the digital side, but don't think we can guarantee anything across varying temperatures and voltages.

-Priyanka

RE: nRF5340 PDM frequency range supported?

Priyanka — Mon, 25 Mar 2024 14:21:13 GMT

Hi Ever,
I will check internally regarding this and get back to you.

Please expect a slight delay as we have the Easter holidays here in Norway and most of the staff are on vacation.

Regards,

Priyanka