Question about the difference between nrf52832 QFAAE0 vs QFFAAE1

[Mikez0]

In our two batch of products, first batch we use the QFAAE0, every thing worked well. But for the second batch the QFAAE1 was used. The issue appeared and its RF performance was very bad. For the BLE advertising monitoring, only scanning for a few seconds. Then no beacon advertising was scanned anymore. The board were in same design, and the firmware were same version. All external components are checked to be correct. If moving the QFAAE0 to the new boards which has QFAAE1, it could work well.

My question, is there any design change from QFAAE0 to QFAAE1? Does it influence the RF performance and BLE TX/RX? Or need any firmware upgrading for the QFAAE1? Thank you, and looking forward to your reply. We are going to move the QFAAE1 to the previous old batch of board to see if it can work.

[Kenneth]

Hello,

There is no change here other than it's a different site that have performed assembly and final test, ref:
https://nrfconnectdocs.nordicsemi.com/pdf/PCN/pcn_195_v1.0.pdf 

We are going to move the QFAAE1 to the previous old batch of board to see if it can work.

Let me know how this tests goes.

You are not writing which SDK you have built your application on, or whether anyone from Nordic have reviewed your schematic and layout. But it could be something marginal is wrong or out of spec here, and this now is visible due to small production variations. If you want we can involve QA so they may perform tests on the two build codes in question to confirm.

Let me know if you want me to set this case to private so you can share information you don't want public.

Kenneth

[Mikez0]

Hi Kenneth, thanks for your reply. The SDK used by our company is NRF connect SDK 2.6.1. We plan to move the QFAAE1 to the 1st batch board to see. When this test finish, I will share the status with you.

[Kenneth]

Sounds like a plan. Based on the description I suspect something related to the crystal, so maybe the load capacitors are not the correct ones for the chosen crystal, and hence may be marginally out of spec, but difficult to comment on at the moment.

Kenneth

[Mikez0]

Your comments gave me some hints. May I confirm my concerns about the low freq(32.78k) and high freq(32M) crystals, the low freq one is related with the tick/timing, the high freq is related with RF performance. So it means the high freq crystal's load capacitors are possible not correctly match, is it so?

[Mikez0]

I have tested to use the internal LC clock instead of using the external 32.768k crystal. There is no improvement on the issue.

[Kenneth]

I would expect the problem is related to the 32MHz yes. I assume you don't by any chance have access to a spectrum analyzer?

Kenneth

[Kenneth]

I suggest make a new private case and share your schematic (e.g. pdf) and layout (e.g. gerber files).

Kenneth