Random power peaks

RE: Random power peaks

Yashodha — Thu, 27 Jan 2022 13:19:49 GMT

These spikes only appear when the device is in advertising mode. When it's connected to the device average current is only a few uA.

And I'm using Sparkfun nRF52840 board with bypassing all unnecessary components.

if it turned off ADC will it save considerable energy?

RE: Random power peaks

Kenneth — Thu, 27 Jan 2022 12:58:58 GMT

They are this way by design, it require on average less current to periodically refresh a regulator than having a regulator ON continously.

Not related to your questions, but if you are measuring on the nRF52840-DK, then make sure you are powering the DK from a steady power supply or battery, I have seen that the USB can cause much noise on measurements.

Kenneth

RE: Random power peaks

Yashodha — Thu, 27 Jan 2022 12:07:18 GMT

Hi, Thank you for your reply.

If it is, how I can reduce those short spikes? any suggestion?

RE: Random power peaks

Kenneth — Thu, 27 Jan 2022 11:52:48 GMT

I suspect it can be that the internal regulator is operating in refresh mode while maintaining system ON mode (e.g. to power clocks and ram). In refresh mode it will draw short "spikes" of current, I would expect this to happen much faster than your plot show, but it can be that the resolution of the power analyzer you are using are not able to measure them all and/or are combining them somehow. The average idle current should be around 2uA, as for instance shown here:
https://devzone.nordicsemi.com/power/w/opp/2/online-power-profiler-for-bluetooth-le

Kenneth