System OFF mode but with 150ms consistent shoot seen in oscilloscope

RE: System OFF mode but with 150ms consistent shoot seen in oscilloscope

kathleenlai — Fri, 28 Feb 2020 01:08:04 GMT

I will flash into the nrf52840DK with the blinky example later on. will be back to you for the outcome. thank for the suggestiong,let's try out.

RE: System OFF mode but with 150ms consistent shoot seen in oscilloscope

Susheel Nuguru — Thu, 27 Feb 2020 11:01:56 GMT

I meant that the chip in itself should not consume any currents apart from the wakeup source configured. All clocks and most of the voltage regulators are switched off. Can you please try to reproduce this just on nordic DK excluding any external things you added. I suspect that this spike comes outside of nRF chip.

RE: System OFF mode but with 150ms consistent shoot seen in oscilloscope

kathleenlai — Thu, 27 Feb 2020 09:40:14 GMT

what do you mean by time of wakeup?

my pulse is consistent on going after sleep.

RE: System OFF mode but with 150ms consistent shoot seen in oscilloscope

Susheel Nuguru — Thu, 27 Feb 2020 07:25:26 GMT

maybe at the time of wakeup , but not during active sleep.

RE: System OFF mode but with 150ms consistent shoot seen in oscilloscope

kathleenlai — Thu, 27 Feb 2020 01:17:23 GMT

Hi Susheel, would that be recharge pulse?

would it be caused by DCDC regulator / LDO regulator?

RE: System OFF mode but with 150ms consistent shoot seen in oscilloscope

Susheel Nuguru — Wed, 26 Feb 2020 13:57:29 GMT

Hi,

there should be no power spikes of that magnitude in system_off mode. Either some external circuit to the chip is consuming the power or the chip has already woken up system off mode.