I found an interesting barrel plug cable. Thought I’d share in case anyone else is looking for a 5.5mm barrel power plug. No clue if it’s any good.

Looks like it’s available in 5v 5A to 28v 5A and the cable will only supply the rated voltage or 5v if the power supply can’t supply the required voltage.

It does have a datasheet, which unfortunately is written in a language I can’t read. Doesn’t look like it comes with a power supply.

I see two issues with it. First, I don’t have a boat load of spare USB-C PD power supplies so this solution winds up costing me more. Second, while the voltage is printed on the cable, it’s printed grey on black so it probably going to be hard to read and once that wears off your back to playing “what’s this cable”.

This cable includes an EMARK chip

This cable is 1.2 meters long

Tip is 5.5mm outer diameter, 2.5mm inner diameter with center positive voltage, but it’s springy so it works just fine for 2.1mm as well.