Single power supply for monitor and pi

[euler105]

Hi

I have attached a Pi 3B+ to a portable LCD (Elecrow 10" HD) using a VESA mounting bracket.
I would like to be able to run one power cable from the wall and split it at the Pi/LCD , supplying 5v to the Pi and 12v to the LCD, rather than running two independent power lines.

Has anyone seen/done something like this?

Thanks!

[k-pi]

It's a nice idea, & I would love to do the same, however, you would need extra hardware that would output the two voltages, & that would add extra bulk to the system - I don't think there is any small power supply that gives out the necessary voltages. If you do find one, please let us know.

[LTolledo]

Mini ITX power supply unit, still bulky and may require a bit of modification, but have both you need...

[Imperf3kt]

Get yourself a 12v #A power supply. Pretty much the same size as the official power supply.
You can get them up to 10A (don't buy from ebay)

Then get yourself a buck converter or a 5v UBEC rated for around 4A.

Finally, get some perfboard and a barrel jack socket to match the power supply.
Solder the jack to the perfboard, strip, solder and run thick wires across the perfboard to create "tracks". One of these runs to a plug or some other connection to the monitor. Split the track somewhere, and solder it to the input of the UBEC, set to ~5.1-5.2v

Exactly how neat the job turns out, and how well it works, depends on your skill with soldering and engineering.

[euler105]

Thanks everyone for your input!

Imperf3kt , I think I will try that. I'll post again if successful.

Thanks!

[hippy]

I don't think there is any small power supply that gives out the necessary voltages. If you do find one, please let us know.

There must be dozens of laptop-style power bricks which take in mains and supply both 12V and 5V at substantial currents which could be used. I'd hit your favourite search engine if I were you.