Libuarte power consumption does not go down after uninit

RE: Libuarte power consumption does not go down after uninit

gaminn — Mon, 24 Aug 2020 18:16:01 GMT

The problem is that libuarte doesn't deinitialize pins. This caused higher power consumption on our board.

RE: Libuarte power consumption does not go down after uninit

Sigurd — Mon, 24 Aug 2020 08:02:45 GMT

Hi,

I have not able to reproduce these numbers you are measuring, so there could be something else happening here as well, but
could you try to replace the nrfx_uarte.c file with the one from nrfx v.1.8.4 ?
github.com/.../nrfx_uarte.c

RE: Libuarte power consumption does not go down after uninit

gaminn — Tue, 18 Aug 2020 08:45:42 GMT

Hi Sigurd,

power consumption with SDK16's nrf_libuarte_drv is 3.5 mA. When I replace nrf_libuarte_drv.c and .h with the one from SDK17 I get 2.8 mA. Obviously, there is some improvement but the problem still persists.

I don't want to switch to SDK17, that would mean heavy testing of all parts of my firmware.

RE: Libuarte power consumption does not go down after uninit

Sigurd — Tue, 18 Aug 2020 07:51:05 GMT

Hi,

From nrfx changelog, we have the following from version v1.8.2:

"Improved the UARTE driver to consume less current after the driver uninitialization. Now all clocks are disabled properly."

Note that SDK 16.0.0 uses nrfx v1.8.0, and SDK 17.0.0 uses nrfx v1.8.4

Can you check and see if you are able to reproduce the issue with SDK 17.0.0 ?

RE: Libuarte power consumption does not go down after uninit

gaminn — Tue, 18 Aug 2020 06:02:28 GMT

This is not the case. It is caused by lib_uarte_async module.

RE: Libuarte power consumption does not go down after uninit

WestCoastDaz — Mon, 17 Aug 2020 21:35:04 GMT

gaminn

If the debugger is connect that will consume several milliamps.