Know this has been asked in the past (circa 2018) but I need some advice at current release levels. Setup is simple: LiPO powered device needs to be charged daily via USB. Charging takes place overnight (like an iPhone) and naturally the device is switched off (in my case, EN → LOW.) Question is, what is best way to ensure charging while Boron is powered off? Would make no sense, for example, to have to power up just to charge, which would lead to unnecessary data charges etc. These are classroom devices used lightly for approximately 5-6 hours daily, then turned off and charged for next day use. Thanks for advice!
The Boron should be charging when EN is low. The EN pin is connected to a load switch on the output side of the bq24195 PMIC. It’s after the charger.
However you should generally avoid using the EN pin when possible and instead only use the software sleep modes (hibernate, ULP, and stop sleep). If you suddenly remove power using EN there is a possibility you could damage the cellular modem.
Great, thanks so much!