5V USB power switch

[VojislavM]

Maybe it would be beater to change the switch part, so the MOSFET Q1 should be triggered by the USB and not the VDD. I think it would be beater this way because the USB voltage is constant, +5V, and VDD is not, it can be from 12V to 50V, and the gate current would not be the same. See the reference picture:

[pointhi]

A possible problem with this approach is the USB Voltage, which could be as low as 4.5V (by specification), and where the diode adds additional 0.3-0.6V drop. Means about 4V at the output side.

No problem for my internal circuit, and I hope the same goes for your circuit on the ProStep Connector. But we should clarify specification first.