RE: Current spikes in Power Profiler Kit

Angry_Oatmeal — Wed, 17 Feb 2021 11:41:10 GMT

Hello Stian,

Thank you for the answer, this makes some sense. I will go ahead and make use of the System On sleep mode using __WFE() to get some more data with the PPK.

Thank you,
Angry Oatmeal

RE: Current spikes in Power Profiler Kit

Stian Røed Hafskjold — Tue, 09 Feb 2021 23:46:00 GMT

Hi, I think the spikes are just switching noise from one of the regulators on the nRF52840 DK, or possibly the USB supply. The blinky example uses a CPU loop to time the LED blinking, which means that the CPU is constantly running, consuming about 3-4 mA. So the current consumption is as expected.

If you want to reduce the current you can use an app_timer to control the LED blinking, and put the CPU in idle. Or if you just want to measure the CPU idle current you can replace the main loop with only a __WFE() call.

int main(void){
    for(;;){
        __WFE();
    }
}

In idle mode you will see spikes as well, every 30-40 ms. This is caused by the internal regulator in the nRF52840 operating in refresh mode, and is normal.