Current consumption

[kb2423]

Hi, 

I tried to monitor current consumption of my device. I used

 

sd_app_evt_wait();

and then used 

 // Wait for an event.
        __WFE();
        // Clear the internal event register.
        __SEV();
        __WFE();

I saw something like this

There are spikes on everywhere.

If I comment out sd_app_evt_wait(); or last __WFE(); it beacomes like that

I am using sdk 15.0.0, before this I was using sdk 14.2 and in 14.2 I was using sd_app_evt_wait function and there was no spikes. How can I fix it?

Thanks.

[Simonr]

Hi

I've tested the ble_app_hrs_rscs_relay example and measured the current using the PPK and the Power Profiler application in nRFConnect for desktop. All tests were made with the same nRF52832 DK and the same PPK. Here are my results:

ble_app_hrs_rscs_relay SDK v15.0.0

As you can see, there are no unexpected spikes here.

ble_app_hrs_rscs_relay SDK v14.2.0

No unexpected spikes here.

ble_app_hrs_rscs_relay SDK v15.2.0

All three are very similar, with no unexpected spikes.

Could you please specify which unmodified example you are seeing these spikes in? I would like you to delete your SDK v15.0 and try downloading a "fresh" one from our Infocenter. Please see if you still experience these unexpected current spikes.

Best regards,

Simon

[kb2423]

Thank you so much for your effort.

When you comment out idle_state_handle function in those examples, lines in your pictures will become more stable. As I said before I was working on ble_app_blinky example before, and there ware no spikes with or without power management functions.

This pictures from fresh SDK v15.0.0

for ble_app_hrs_rscs_relay

with  idle_state_handle function, 

without  idle_state_handle function.

for ble_app_blinky

with  idle_state_handle function, 

without  idle_state_handle function.

As you see there is no change in ble_app_blinky but there are changes in ble_app_hrs_rscs_relay example that's why I thought those spikes are unexpected.  Thank you.

[Simonr]

These are just calls that check for idle_state_handle I think, and won't be anything to worry about. I'm sure you do see the change in avg. current consumption with and without idle_state_handle though.

Best regards,

Simon