NRF9160 power consumption 1,400uA higher with MCUBOOT enabled

[GJSea]

Hi,

The baseline PSM sleep current of our device with all of the additional support circuitry is 100uA, and have just integrated FOTA capability. 

However when we set CONFIG_BOOTLOADER_MCUBOOT=y the PSM sleep current jumps to 1,500uA, so 1,400uA greater than when CONFIG_BOOTLOADER_MCUBOOT=n. We switch it back to 'n' and the current is back to 100uA again.

I added CONFIG_SERIAL=n to ncs\mcuboot\boot\zephyr\prj.conf which resulted in no change.

Any recommendations as to what us drawing the 1,400 extra uA and how to turn it off?

Thx!

[Stian Røed Hafskjold]

Not sure what exactly is drawing the 1400 uA current, but there seems to be an issue with configurations being overwritten by MCU boot, and that you need the same .overlay file in both application and bootloader. Can you try out Didrik's answer here? https://devzone.nordicsemi.com/f/nordic-q-a/49823/project-does-not-do-serial-output/200105#200105

[GJSea]

Hi Stian,

Wow this did the trick!!

Thanks so much!