3.3V Output External circuitry may draw up to a total of 50mA max current from the 3.3V Out pins. Is maximum current from 3.3V pin really 50mA? IO Pins All IO pins are 3.3V, not 1.8V.  Pins are not 5V tolerant. Full details are available here Max Current Maximum 16mA per IO pin with the total current … Continue reading Model B IO Pins