Goal: I wish to power 3 Raspi. I am currently running 3 USB C wires powering the device, but I wish to build or find ways to power them all using GPIO header power pins.
Background: Mechanical engineering student who is learning electrical engineering via online circuits and books
Constraints: 3 Raspis 5V/~2.5A
Current Readings: Since all uses 5V power, I understand that I require a 5V regulator and RPI max currents sum up to 7.5 amps, or let's say 8 amps. And since I am trying to use GPIO pins, which don't have overcurrent protection, I should design one as well(?)
- Would It be ok to power all of them using 5V 8A switch mode regulator in parallel?
- Would I require over-current protection? What would be a workable circuit? Do I need them in all three?
- What would be the initial source? AC-> DC -> DC5V ? or DC24V -> 5V? Would it be better to buy 5V 8A power jack adapter? and plug directly to the Raspis?
- If the Pis are in an Idle state, what happens to the currents?
- What more protection would I require?
Outro I read through many electronic engineering books, but I could not find a good solution to this situation. I would really appreciate it if you could even shine any light on this matter. Thank you.
Edits +a I was under weather after the cold. Sorry for not responding sooner. I understand that you can power RPi through one of the Power lines in GPIOs, which bypasses the internal voltage regulator. This method is similar to those PoE hats, or any other powering hats. (@SamGibson is right.) The main goal was to save some money on the type C plug and try to power through a self-built board.