[SOLVED] Power supply for Raspberry Pi

NJackson7

Prominent
Oct 26, 2020
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510
Hi all. I recently got a Raspberry Pi 4 model B with 4gb RAM along with the official Raspberry Pi 7" touchscreen display. I have set it up and it launches as it should, but i get a message on the desktop saying "Low voltage warning, please check your power supply." I am using a PSU that says it works at 5V/3A as I had heard that 5V is the recommended amount for Pi 4, but i was wondering if i needed any higher as the power is being shared between the pi and the touchscreen through the 1 cable.

Many thanks.
 
Solution
The PSU can only supply 3A (@5V) = 15 W)). RPi requires 3A (@5V) =15W) The supply you have can only supply enough power for the RPi. period.

The display requires power, too. Find the power requirements for the display. Get a new PSU that can power both.

OldSurferDude

Reputable
May 18, 2019
168
30
4,640
I see that the RPi4B draws 3A. Find out the current required for the display. Add the two currents together, double it and find a PSU with that provides that current (@ 5V)

Why the double? There are a lot of very cheap PSUs that do not perform to their stated specs. Once you start dragging them down, they can have nasty noise issues which could render your Pi non-functional.
 

NJackson7

Prominent
Oct 26, 2020
17
0
510
The way i currently have mine set up, i only have a power cable going into the Screens power input, this power then being shared over the GPIO pins. Would my issue be fixed if i found a splitter so that i could get the 1 plug connected to both boards (e.g. a usb-c for the pi and a micro usb for the screen)?
 

OldSurferDude

Reputable
May 18, 2019
168
30
4,640
The PSU can only supply 3A (@5V) = 15 W)). RPi requires 3A (@5V) =15W) The supply you have can only supply enough power for the RPi. period.

The display requires power, too. Find the power requirements for the display. Get a new PSU that can power both.
 
Solution