Excessive current consumption when RTC running.

RE: Excessive current consumption when RTC running.

Einar Thorsrud — Mon, 20 Aug 2018 05:57:05 GMT

Hi,

The RTC should not cause this high peak current consumption (6 mA). Are you confident that the measurements are correct? Assuming they are, and as you see it varying depending on the RTC configuration, I wonder if you might be seeing some interrupts that you perhaps have not expected, and that you spend some time processing them. You could get a current consumption in that order if the CPU is active. Can you upload the code that you use to produce this behavior?

RE: Excessive current consumption when RTC running.

Valerii_Ie — Thu, 16 Aug 2018 15:21:42 GMT

Hi Einar,
The distance between pulses is always near 17ms. I assumed that it RTC related because If I increase RTC sleep interval the distance between pulses increases proportionally.
Please see attached zoomed plot. I'll start preparing code for revision.

RE: Excessive current consumption when RTC running.

Einar Thorsrud — Thu, 16 Aug 2018 12:23:54 GMT

Hi,

The spikes you are seeing do not look like the LDO refresh mode. Looking at the graph you posted, they seem to be about 20 ms apart and almost 1 ms long. This is way too wide and with a too long distance in time for refresh mode. It looks like you are using the CPU or similar. Can you make a plot that zooms in (in time) on a single spike? It would also be very useful to see your code.

RE: Excessive current consumption when RTC running.

Valerii_Ie — Thu, 16 Aug 2018 07:48:23 GMT

Hi Aryan, I found similar figure on devzone. https://devzone.nordicsemi.com/f/nordic-q-a/24324/power-consumption-spike

Also I tried to disable all peripherals on board and to catch any retated interrupts. No result for now. If this spikes are normal operation of ldo oi wonder if any official doc can give detailed description of dependencies to make one understand how frequency of this spikes can be adjusted.

Thanks

RE: Excessive current consumption when RTC running.

Valerii_Ie — Mon, 13 Aug 2018 11:43:36 GMT

Hi Aryan, yes I use custom board and can't publish code. However rtc functionality is based on RTC example taken from sdk 15. Chip marking: N52832 QFAAE1 1812AJ

Also current plot:

RE: Excessive current consumption when RTC running.

Susheel Nuguru — Mon, 13 Aug 2018 11:31:04 GMT

Valerii, are you testing this on a custom board? if so which version of nRF52832 exactly are you using (can you give the lazer markings)? 6mA is too high for just RTC . It seems that something else is also running in the background and it is not just RTC as you seem.

Can you attach your code here, so that i can do a quick test on my desk?

RE: Excessive current consumption when RTC running.

Valerii_Ie — Fri, 10 Aug 2018 15:33:11 GMT

Hi Aryan, what pin number do you mean?

RE: Excessive current consumption when RTC running.

Susheel Nuguru — Fri, 10 Aug 2018 12:45:10 GMT

I am curious to know if there are any other parts of your code logic that depends on the define of N ticks? Can you show me your power consumption analyzer snapshot to see the spikes nature?