MiSTer FPGA Forum

Hey guys, kinda off topic but not, Im hoping I can get advise from those that are smarter than me.
Im thinking of building a portable mister arcade case and would like to power the Mister and Display with this.

https://www.amazon.com/gp/product/B08JV4W4NY/

Where I hesitate is where some ports output multiple voltages, and I do not understand how it "knows" what volts\amps to apply. Maybe its as simple as the the device trys to pull more it gives more, but I dont know.

Has anyone used this or other similar devices to power Mister?

The usb C ports on that battery support USB-PD protocol (Power-Delivery?). This protocol allows the psu to negotiate the correct supply voltage with the connected device. Thats why you see 5/9/12 volts as options on that port, if the device asks for 12v, that's what it'll get.

If you plug a "dumb" device that doesn't support USB-PD into those ports, you'll just get 5v.

Thanks for that info and thats what Mister uses, so it seems like the Volts and amps would be fine.

The Mister doesn't speak any power delivery protocols, and requires 5V input on the barrel connector, ideally at 4 amps. I'm not sure that supply would put out that much amperage without negotiation, which the Mister can't do. Port 4 might work, with an adapter to the barrel plug, but no promises.

You can buy very cheap USB PD charging boards that will negotiate the power output. Something like THIS.
This was the first one I found - don't treat the link as a recommendation. If you are not that money starved, you can surely find something less sketchy on Mouser or Digikey.

As for the power bank itself, I have this exact one. I have been using it with Nintendo Switch for more than two years and it did not die or set anything on fire.