[Solved / Archived] Raspbetty Pi Zero W USB max load

Witty Pi 4 Mini uses AO4620 as MOSFET switch, whose Rds(ON) is about 50mΩ under 5V. That means when drawing 2A current via this MOSFET switch the voltage drop will be about 0.1V. Considering there is also voltage drop on wires and copper trace, the actual voltage drop will be bigger.

Don't know how much current does your GoPro draw, but if it can't switch on, most probably the input voltage has drop so much that the voltage actually apply on GoPro is too low to turn it on.

Witty Pi 4 Mini is designed to output up to 2.5A for Raspberry Pi and its peripherals, please make sure the actual current consumption is within this limit, and also your power supply can actually delivery this much current -- otherwise its output voltage will quickly drop according to the increasing of output current.

Thanks for the reply. The GoPro will turn off if the power source do not provide 2A. Even if the Pi Zero should not limit the current on the USB, if I connect the GoPro to the Pi without the Witty Pi it turns on but still detects low current. So I believe that there are 2 problems, with or without the WItty Pi. But the GoPro works id I connect it through a USB HUB HAT powered externally. I was wondering if there is a way to still use the Witty Pi but power the Pi through a MOSFET directly from the power source.

@marcot77 you can use the +5V pin on your Pi as a signal to trigger a MOSFET to control your GoPro's external power source.