Hi,
I’m using an RP5. It is connected via a super big home made cable to a 10A power supply.
When I start it says the power supply is inadequate and it will restrict USB power. I have stuck a voltmeter to measure the output of the power supply and it never stops below 5.1 during boot, or indeed ever.
Before I start again with making a cable: maybe my soldering wasn’t good enough etc. I thought I’d check how does it know the power supply is inadequate?
The power supply and wire are both overkill and I thought my soldering was okay. It was only adding a 4 pad USB male connector to a wire, so not exactly complicated. I put shrink plastic on that end so I can’t measure the voltage there. Maybe there is a resistor on the USB-C which tells it the amperage is limited?
There is some potentially helpful documentation here -
Powering Raspberry Pi 5 - https://www.raspberrypi.com/documentati ... erry-pi-5
In short: USB Power Delivery. The firmware in the RPi5 and the official recommended Power Supply are 'smart' and talk to each other. The quality of your soldering cannot replace that. There is no 'measurement' taking place.
Lots and lots of previous, sometimes contentious, discussion has taken place on this topic.
{Edit: to acknowledge asynchronous overlap with the response from a Moderator. Left for emphasis.}
Statistics: Posted by B.Goode — Tue Feb 06, 2024 11:31 am