Im designing a small board that with have an input 220VAC and with an AC/DC module will generate the 5V for my 5V components and then with a regulator I generate 3.3V for my 3V3 components.
There will be also and a usb to uart interface for development purposes.
The way im going to use this board is firstly with the usb power supply I will power all the components. Does the AC/DC module need a protection for reverse current on its output?
And secondly while the board is working via the ac/dc module, I may need to plug the usb to programm the board. Is it safe or I need some kind of protection in that case too?
Thank you for your advice. I think I will implement an ideal diode OR-ing but with a quick simulation it seems that it doesn't block reverse current in my case. Simulation Here I think this circuit is for reverse polarity protection? I need reverse current protection?