nRF52 idle current in Zephyr when RTT is enabled

RE: nRF52 idle current in Zephyr when RTT is enabled

Kazi Afroza Sultana — Thu, 06 Oct 2022 13:53:53 GMT

Hello,

The spikes might come from the internal regulator of the PPK2 or USB noise. Can you say details about your setup?

Thanks.

Kazi Afroza Sultana

RE: nRF52 idle current in Zephyr when RTT is enabled

Thanos — Tue, 04 Oct 2022 13:56:56 GMT

Hi,

It seems that the offending line is the following.

CONFIG_SHELL_BACKEND_RTT=y

After changing to 'no' current dropped to the expected levels (alsmost).

Now I have to find out where these mA spikes every exactly 4 seconds come from, even in Blinky application, that raise consumption from 8uA to 10.5uA. They do not look like LDO refresh, more like a thread timeout (?) Does this number (4s) ring a bell?

Anyway, since RTT logging can be enabled without power penalty, then it is not a problem to leave RTT shell out.

Thank you

RE: nRF52 idle current in Zephyr when RTT is enabled

Kazi Afroza Sultana — Tue, 04 Oct 2022 06:04:12 GMT

Hello,

Can you try to reproduce this with Blinky example to se if it shows same value? Then it might be bug. You can try and let us know again.

Thanks.

Best Regards,

Kazi Afroza Sultana