Under voltage lockout when running from LiPo

[Chris]

Dear all,

It's strange that this seems to not have been asked before... since the nRF52840 can be powered directly from a LiPo battery, I wonder if there is an UVLO protection.
If not, could I help myself by using a voltage detector which pulls nRESET low if Vbat < 3V (for example)? If nRESET is low, does it mean, that the device is "switched off" ( = no load)?

[haakonsh]

There's no UVLO for batteries on the SoC. I suggest you use the Power-fail comparator. When an under voltage state is detected you put the SoC into SystemOFF to draw a minimal amount of current. 

If you hold the reset pin you will draw a lot of current as the SoC is stuck in a non-low power state. 

[Chris]

Awesome, thank you for pointing me in the right direction!