How to handle the DC charge input on the PCB for a symmetrical 5V magnetic charger cable?

Question

I'm working on a low voltage DC consumer product that specifies using a specific magnetic charge cable on the 5V input instead of a regular USB connector. See image:

We started out assuming the cable wasn't symmetrical and there must be a positive and ground that could only fit one way, so we planned to just use a corresponding positive and ground pin on the PCB power input. See image:

But later we found the cable is in fact symmetrical, so the user could attach it in an orientation where the positive and ground connections could be swapped. So, we can't just assume to have a static positive and ground pin as shown in the pictures, it seems we need a way to sense upon connection, which pin is positive and which pin is ground and design our circuit to handle it either way.

Are there IC's we could use to help handle this? Some other approaches to the circuit design?

Thank you!

Note: all the images here are my own.

Answer 1

Seems the below two circuits are two ways to handle this, using either four MOSFETS or four diodes, with the MOSFET solution preferred as it results in a lower voltage drop.

Answer 2

Put a magnet in your product that "helps" the user "fix" the cable in the right orientation. If "correctly" aligned, the connector won't flip-off because the magnetic alignment of the two parts will physically enhance the electrical connection. If the alignment is incorrect, the two parts will automatically disconnect unless someone is holding them closed.

Then, as a final circuit protection feature use this: -

Image taken from here, another SE question/answer. If the incoming supply is correct, the P channel MOSFET turns on and allows normal operation. If the incoming supply is incorrect then the bulk diode in the MOSFET does not allow conduction and, due to incorrect gate-source voltage, the MOSFET will not turn on.

Or, just use the above circuit and forget about the magnet and let users figure out how to orientate the connector themselves. The important thing here is circuit protection (as I see it) AND, minimizing MOSFET conduction losses hence, I favour this rather than diodes (high conduction losses) or MOSFETs wired in a bridge (two lots of conduction losses).