LPCOMP current consumption

[alyssiarosewhite]

NCS 2.5.2

Toolchain 2.5.1

NRF52840

Hi,

I'm currently power profiling our custom board.  So far I've managed to get the current consumption quite low (6.5uA at 3V), but my one hiccup at the moment is enabling the LPCOMP.  It increases the consumption by around 17uA.  I can see in previous posts that other people have made the same observation (this one in particular). I was wondering if any changes were being made to NRF52840 in future revisions regarding pulling this in line with the NRF52832 in terms of current consumption.

Putting the system into SYSTEM OFF isn't an option for us as we need RAM retention but also wake on LPCOMP.

Any ideas are welcome.

Thank you

[Kazi Afroza Sultana]

Hello,

This is a HW limitation and it has not changed in later versions of nRF52840. The power domain required to keep LPCOMP enabled in SystemON is much larger than in nRF52832, causing the increased current. LPCOMP is primarily designed for use in System OFF.

So, you cannot keep the system ON and simultaneously keeping LPCOMP on to get desired current consumption.

What are the latency requirements?

[alyssiarosewhite]

Hi Kazi,

Okay so the previous statements from 6+ years ago still stand, thank you for checking.

My problem with System OFF is that there doesn't seem to be an option to keep RAM retention and also wake on LPCOMP.