USB backfeeding power in

[chrissbarr]

USB 5V - diode drop is wired to VDD in. On a 5V control board this could be annoying, on a 3.3V board this could potentially do damage?

Not sure if this is important? Board isn't intended to have USB connected while in place, really just for firmware updates. Maybe later firmware will add some other use for USB (data out, configuration etc.)?

Probably need an extra diode on the VDD in line. Not sure how the voltage drop will impact things when powered from 3.3V, already dropping a little through the regulator.