Can't find difference in sleep current

[StartechLuke]

We have an application where we want it to go to sleep, but still check things periodically, retain registers, and whatnot; and as such power-on is a good fit. However, it's drawing too much power, if we set it to power-off we're seeing about 520uA less than power-on that I can't account for. It's not in debug mode, it's in low-power mode for sleep not latency, the gpio should be set correctly, peripherals should be turned off, and I've turned off ble advertising.

Is there something else on the ble that I should be turning off (we don't need it while asleep)? is there any way to check if peripherals are still on? Am I missing something obvious?

[Einar Thorsrud]

Hi,

There must be some peripheral still active on the device since it consumes about 0.5 mA. Have you tried to narrow down what this could be by commenting out most of your code (use of peripherals etc.), and adding gradually back to see which change leads to the increased sleep current?

[StartechLuke]

I figured something was still on, but am struggling to find it. I have tried commenting out/not even initializing the peripherals we are using, but none of them appear to be the culprit, as far as I can tell the only thing still "on" is the ble/peer manager...

We're using sdk12.3 and soft device s130 if that makes a difference, and are using a external crystal for the LFCLK

[StartechLuke]

Ok, so I figured it out, we have an app timer that we are using to implement mills() and run the main loop that's ticking over every 1ms, and we need even when asleep. So now what I'm doing is changing the timebase to 10ms when it goes to sleep and back to 1ms when it wakes back up, and that shaves ~0.5mA off the sleep current. Thanks for your help!