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Raspberry Pi 4 - USB design fault

This article may be of interest to anyone contemplating buying a Raspberry Pi 4:

Interesting, thanks for the link. The Pi4 works with all the USB-C chargers I’ve tested it. Obviously the chargers I’ve use are not smart enough! Since the Pi only requires 5V 3A it doesn’t make sense to use a more powerful and expensive smart USB-C charger which can output up to 20V 5A.

Unless you have something attached to the Pi’s USB ports that draws more than just a small amount
of power from the Pi. e.g. a hard disk drive.

To be fair though, that issue can be resolved with a powered USB hub.

The Pi’s USB-C cannot handle more than 3A 5V, the Pi does not use USB-C PD which is the protocol require for higher than 5V operation.

There was a good technical analysis of the issue on hackaday Exploring The Raspberry Pi 4 USB-C Issue In-Depth | Hackaday

Implementing USB-C correctly does seem rather tricky.

That article was from 2019, there’s this article which suggests it was fixed in early 2020, and all boards should have the updated revision now.

Good advice if you’re buying old stock though!

The article Robert linked to indicated the problem was the use of one resistor where two resistors should’ve been used. Sounds more like an attempt to keep manufacturing costs down, more than anything else. Then again, it could’ve simply been something that was overlooked.
(I have a bit more difficulty believing it was the latter reason)

Or updating/repurposing an early version.

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