Differences in nRF51 chip versions

RE: Differences in nRF51 chip versions

Hung Bui — Fri, 17 Nov 2017 16:22:40 GMT

You may want to request support from the module maker. A sniffer trace would tell if there are a lot of packets drop causing connection timeout.

RE: Differences in nRF51 chip versions

Hieu — Fri, 17 Nov 2017 02:59:09 GMT

By module I meant one like those listed here. The ones we used are designed and manufactured by a local business and is not listed there, however.

I also reviewed the reference you linked and this blog post. If I understand the procedure right, I think we could only hope that the module manufacturer followed reference design and tuned their antenna. But if there is any guidelines that we should followed in this situation, or if I am having any misconception, please advise me.

RE: Differences in nRF51 chip versions

Hung Bui — Thu, 16 Nov 2017 14:57:48 GMT

Yes, the RC oscillators shouldn't be a problem here. Same firmware should be able to run on both chip (if the size fits). I don't understand what you meant here "modules that integrate both the nRF51 and PCB antenna, so I think those issues cannot be helped in our case"

The reference design is made to be used with PCB antenna (as well as other antenna). It should be followed. You should only modify the component values if you do have equipment to tune and match them with the design and material of the product.

RE: Differences in nRF51 chip versions

Hieu — Thu, 16 Nov 2017 13:30:22 GMT

We are using modules that integrate both the nRF51 and PCB antenna, so I think those issues cannot be helped in our case. But if there are still things that has to be adjusted, please advise me, and I will forward it to our PCB designing engineer.

From your answer, I take it the RC oscillators are the same in the two chips? My supervisor kind of want me to be sure about that, aside from finding out what else is wrong with the current design.

RE: Differences in nRF51 chip versions

Hung Bui — Thu, 16 Nov 2017 13:15:31 GMT

Have you followed the reference layout for the QFAC ? The matching network components values are slightly different between QFAB and QFAC. Please take a look at the reference design here.

Also make sure your antenna is tuned properly to have good performance.