I’m designing some laser-cut cases for my T-beams and was thinking of re-routing / mounting a second USB connection out the side or back of the case. Before I fry something, does anyone know if the GND and 5V pins next to the USB port are “in line” with that port & the charge circuit? If I applied power to those pins instead of the USB port, would the board power up and charge the battery? Maybe GND and VIN are the way to go? I can’t find a good reference for those pins, or at least one the speaks to external power specifically.
I know I get 5 volts out of the 5V pin when the USB cable is plugged in, but not sure how comfortable I am feeding power into the board that way, since it’d take me a month to get a replacement. Haven’t metered the VIN pin yet, I just now noticed that it’s there.
I don’t know off the top of my head, but I did check in the full schematic for the TBEAM 1.0 into docs/hardware. I bet that would help you probe it out.
From my testing the 5V pin is only 5V when USB is connected, otherwise it is VBAT regardless of power state if a battery is inserted. Unfortunately you won’t be able to break into the USB VBUS power through those header pins as they are connected to VSYS (TBeam schematic) or IPSOUT (APX192 schematic). Unfortunately the TBeam doesn’t break out the ACIN pins either which would solve your problem easily!
You could solder across the capacitor C8211 as it sits across VBUS and GND. I’d upload an image but it isn’t letting me at the moment. It is the big one on the left, up from the USB connector.
Haven’t metered the VIN pin yet, I just now noticed that it’s there.
