Official RPI 7'' Touch screen power requirements ???

Hi,

The display consumption alone is about 550mA at 5V.

With my Pi 3B attached to it, I see about 750 mA total power consumption (Pi + display) when the Pi is idling and not attached to anything else, and with a WiFi connection to a network but not transferring anything. You can use online Pi 3B and Pi 4 supply current consumption measurements done by others to extrapolate.

However, to actually start up the Pi 3B with the display, current bursts to beyond 1100mA need to be supported by the power supply for the Pi + display. And once the Pi is running applications then of course the overall current consumption of the Pi and Display can exceed that.

If you're getting a power supply related issue you'll need to use an 'official' Pi power supply, because it outputs slightly higher voltage of 5.1V, not 5.0V, and has heavier gauge wire to reduce the voltage drop at times of high current demand.

If you're running a high load from the Pi's USB connectors or 40-way connector, then you may need to investigate other ways to power the peripherals independently. So, for instance, a USB keyboard or mouse would be fine, but a USB powered spinning drive might not - it's experimental because there is no datasheet specifying the precise limit, it's a low-end consumer product.

[admin : I always have to reset my pass to be able to login, afterwards my login/pass never works]

I use the official power supply with nothing else connected to the RPI4 but that screen

actually , the first time I saw that firmware warning was right after installing the screen (which is powered from 5V/GND from the GPIO)

thanks for the infos

I see; that could be related to the Pi's software image (the alert threshold could have been tweaked in firmware) or could be benign if you're just on the edge due to tolerances. If there's non-critical things stored/running on the Pi then that may be good enough for some scenarios. Otherwise there is a way to power the display from a separate supply although that can be undesirable sometimes. I can't really suggest much more, my Pi 4's are not connected to that display unfortunately.

yeah I thought it was odd since it is supposed to be the official RPI screen, yet again the RPI4 seems picky on the side of it's power supply :-)

hello,

I have found that a Apple 12w usb power supply, has been suffecent supply for any PI project that I have attempted. I have only my pi 4 a few weeks now so have not had time do much with PI 4 but using Apples 12w supply, I have never had power warnings or problems to date, again I have limited experience with PI 4 but chances are you already have  one around the house/shop so it can be a easy to access and good solution to power issues if nothing else its worth consideration. Hope this helps

I use GPIO power with my Pi4 and there's not been a problem. USB isn't good on the other hand.

I just completed a project that used the OEM Pi 7" screen and Pi3B+ running bookworm. I experienced no power issues.

A number of years ago I made the decision to only use OEM Pi power supplies. I found that the aliexpress 3.0Amp spec'd power supply just didn't cut it. Sometimes they worked and sometimes I would catch a flashing power supply warning. Occasionally a screen warning.

The cost of OEM power supplies is greater compared to aliexpress. Using the OEM rated power supply ensures me that I have don't have to chase power supply issues.

That reminds me, I need to order some Pi power supplies.