3.3V LDO regulator circuit reverse polarity protection

[ilium007]

Does this circuit look correct? I am building this power as a power supply for an ESP32 project and want to have both a USB-C power input and a 5VDC screw terminal input. I need reverse polarity protection on the screw terminal input.

Q1 is a logic level P-channel mosfet (https://datasheet.lcsc.com/lcsc/1810180217_Alpha-Omega-Semicon-AO3401A_C15127.pdf) with a low -2.5 Vgs and relatively low 80mΩ Rds.

Does this circuit look correct? Will this also give the USB-C input preference over the screw terminal input?

[wraper]

Since you are using LDO and don't need full 5V, you can just use a Schottky diode from each input and not overcomplicate things.
EDIT: Your circuit is susceptible to ESD damage.

[ilium007]

Will do, thanks. I was trying to be clever 

[ilium007]

This should work??

[wraper]

Yes but you don't need 10k resistor unless you are using VBUS detection somewhere else.

[ilium007]

Yes but you don't need 10k resistor unless you are using VBUS detection somewhere else.

I missed that one. Thanks.

[Peabody]

However, there is no preference in the diode circuit.  The power source with the highest voltage will power the load.  In your original circuit, if USB power is present, it will always power the load unless the screw terminal source is high enough to forward bias the mosfet body diode.  But if preference is important, you could still use the two-diode circuit, but make the screw terminal diode a regular rectifier diode.