LOW POWER SYSTEM ON SLEEP XIAO BLE NRF52840 Blinky

RE: LOW POWER SYSTEM ON SLEEP XIAO BLE NRF52840 Blinky

ray78654 — Thu, 25 Jul 2024 19:30:49 GMT

Just an update on this - I switched out to a custom board I had made (uses a nina b306) and for the most part I was able to get the current draw down to approximately 10uA with the same code. I'm not entirely sure why this is but, I assume there are some hardware features on the XIAO that I have either overlooked or neglected to toggle. Despite searching for a specific cause I have found nothing worthy of note. Regardless, a large bulk of the issue seems to have been resolved using the custom board.

A second issue of further power optimization to get around 2-5uA still needs to be done but I'm fairly confident this can be achieved by using some tips in the power optimization guide; placing external flash into sleep mode is something I feel would do the trick but I am yet to test this.

RE: LOW POWER SYSTEM ON SLEEP XIAO BLE NRF52840 Blinky

Naeem Maroof — Fri, 12 Jul 2024 15:51:07 GMT

Hi,

I see that CONFIG_PM is only supported by some board, details of which you can see on KCONFIG reference.

And the guide that I have link suggests to use the CONFIG_PM_DEVICE that is available for your board.

Other than that, and following the guide, I don't have any other suggestion.

RE: LOW POWER SYSTEM ON SLEEP XIAO BLE NRF52840 Blinky

ray78654 — Mon, 08 Jul 2024 13:40:45 GMT

Hi Naeem!

Thanks for that, I am using SDK version 2.7.0.

More or less everything that is not in use is turned off which I can confirm - including additional peripherals. The guide if definitely helpful but unfortunately hasn’t helped at solving this particular issue.

RE: LOW POWER SYSTEM ON SLEEP XIAO BLE NRF52840 Blinky

Naeem Maroof — Mon, 08 Jul 2024 13:16:19 GMT

Which NCS version you are using?

The first thing would be to check that the modules you are not using should be off, like uart and logging etc.

But looks like you have already done that. You may confirm it from ./build/zephyr/.config file.

You may also like to disable peripherals that you are not using, e.g adc, or spi, or other hardware peripherals that you can configure using overlay files.

The power optimization guide might also be helpful.