It is clear that a Pi4 will not negotiate a higher voltage.Hi-Power USB-C chargers are wasted money on a Raspberry-Pi.
These devices require a software handshake to deliver more than 10W (2A-5V), and would do that by increasing the output voltage above 5V up to 20V.
Obviously the Raspberry Pi neither delivers the handshake, nor can deal with more than 5,5V.
But where do you get that 10W from?
All 'normal' USB-C PD PSU's I have can do up to 3A at 5V, so 15W. Indeed a power sink device that can work with higher voltages likely has some internal threshold or whatever decision making that it will request higher voltage if higher than 15W is expected.
A Pi5 can use up to 25W at 5V. Does it negotiate something or just silently draw more than 3A if some external USB device makes it pull more than 3A?
Note that a Pi has no own battery like a laptop, so cannot risk a show off/on if that would be the case for USB-C PD.
Statistics: Posted by redvli — Sat Oct 05, 2024 7:47 am
