LF Clock calibration problems (nRF Connect SDK 1.9.1)

RE: LF Clock calibration problems (nRF Connect SDK 1.9.1)

ovrebekk — Mon, 25 Apr 2022 11:12:52 GMT

Hi again

Apparently the bug has been solved in the upstream repositories, and is covered by this pull request.

Are you able to check it out, and see if it solves the issue on your end?

Best regards
Torbjørn

ovrebekk — Tue, 22 Mar 2022 13:20:59 GMT

Thanks for the confirmation. I have reported the issue to the software team, and will let you know once I hear back from them.

As a temporary workaround you could try just to disable the automatic calibration, and triggering it manually through the CAL task.

Essentially you just need to trigger this task on a timer every 8 seconds.

Best regards
Torbjørn

Allan P — Mon, 21 Mar 2022 12:36:13 GMT

Hi,

That's totally the problem, on my screenshots there is some noise, but it's about 400µA

Thanks.

ovrebekk — Mon, 21 Mar 2022 11:37:04 GMT

I tried reproducing your issue, and it seems I am seeing something similar:

After doing calibration the CPU gets stuck in a state where it draws ~400uA, until the next advertising event occurs.

I will report this issue to the software team so that they can have a look at it, and try to get you an update by the end of the week.

Best regards
Torbjørn

Allan P — Fri, 18 Mar 2022 11:05:51 GMT

The big problem is when I space more the advertising :

Most of the time are used for nothing, consuming the battery...

Without this problem, with external crystal I got around 5µA.

It's normal that the calibration takes some more, but in my case the CPU is just wasting all is idle time doing nothing (stuck somewhere)

ovrebekk — Fri, 18 Mar 2022 10:43:10 GMT

Looking at your plot it seems the average current is around 57uA, which doesn't sound too bad.

Do you know what the average current was when you tested using external LF crystal?

Have you compared the numbers to what you get with the Online Power Profiler (using comparable settings) to see if your results are excessive?

Best regards
Torbjørn