Boron CHG light flashing rapidly and not starting


Hey All,

I have a Boron communicating with an Itsybitsy M0 over the I2C bus and everytime I power the boards up at the same time the boron CHG light starts flashing rapids and it will not start. If I start the Boron first and then start the M0 after everything comes up and they communicate correctly. Any thoughts on what would be preventing the Boron from starting? I know that the power ic and fuel gauge communicate over the I2C so I’m wondering if that is somehow related.

I really appreciate your input. Thank you!


It sounds like your power supply cannot supply enough current to start up both boards at once. The Boron charge light flashing indicates not enough charging current. Take a look at your power supply and consider increasing available current to the boards.


Thank you for the suggestion. I think that I’ve been able to track down the issue. It seems to be related to a busy line that I had configured that was sending an output to a pin on the Boron. The same power supply has been used on other PCBs without issue. It is still somewhat of a mystery, but the issue hasn’t presented itself since the change. Hopefully at some point the U8G2 SOS issue will be resolved then I can remove the ItsyBitsy that is driving the display.