nrf5x part numbers

[George]

I guess this has been mentioned/asked before but you should really do something to enforce the full chip part-numbers to be listed at distributors.

For example, for an older design I have an nrf51822-CEAA. Looking at the compatibility matrix this same part-number exists in all 3 revisions of the chip. Granted that the marking on the chip will tell you the exact revision but when ordering parts it is a total nightmare and just leads to confusion and unnecessary delays. Honestly I've never came across such a misleading part numbering method and it is too bad for a product that is really so good in many aspects. The part number shown by distrubutors is just nrf51822-CEAA with no indication of chip revision. Handling the order via turnkey suppliers becomes even worst. Last year I had a similar issues with the nrf51822-QFAA, I wanted the latest version but got V1 parts! - the only real solution I found in that case was to change to the nrf51822-QFAC which exists only as V3 just so I'm sure to get the latest revision.

For the nrf51822-CEAA, I was thinking to use the CTAA instead to avoid the problem but this doesn't seem to be stocked anywhere so most likely I'll end up having to order a few thousand nrf51822-CEAA chips and just hope I get the last revision!

The same problem seems to exist with the newer nRF52 chips.

[Wojtek]

I think you should ask supplier about that, but if you are buying from some popular suppliers (like mouser or digikey etc) there is a little chance they still have old revision chips - I really doubt it. Markings on nrf5x chips are really clear, but they are just not fully shown in the product info on suppliers sites.

There should be no problem with nRF52832, as there is only one version (revision 1) which is sold as separate chips till now.

[George]

If I'm ordering parts myself I can ask (although still not always a guarantee), but most of the time the ordering is handled by third parties and somewhere down the supply chain the issue with different revisions can be overlooked. This is just what happened to me on the nrf51822-qfaa, nobody picked up the wrong revision and we ended up having to rework many boards. Yes the marking on the chip is clear, but by the time I can read the marking on the chip its just too late :) ...if I have to read it at all it probably means I have a big problem at hand! Yes true with nrf52 there is only one revision but already the revision is not indicated at distributors so when a new revision comes out we'll likely be in the same situation.

[Wojtek]

Yep, that is true. I wonder how other IC manufacturers approach to that problem.

[George]

Well, in reality this problem is not exclusive to Nordic, other manufactures have similar problems but for some reason in 20 years the only other parts I remember having similar issues with were the atmel xmega when they were just released (they had a lot of bugs at the time),I think they had changed partnumbers for the most problematic parts. Digikey often has PCN documents specific to the orderable part but I don't remember seeing this for Noridic devices. Some other parts such as atmel SAM processors have a revision code within the main partnumber. I think the issue is more pronounced with the nrf5x because of the softdevice in/compatibility to specific chip revisions. With full custom code the differences between revisions are less likely to be a problem. Also most other devices I tend to use are more 'seasoned' so different revisions will only have minor changes.