this post was submitted on 24 Mar 2025
178 points (100.0% liked)

AssholeDesign

8555 readers
1 users here now

This is a community for designs specifically crafted to make the experience worse for the user. This can be due to greed, apathy, laziness or just downright scumbaggery.

founded 2 years ago
MODERATORS
 

I just went to charge my kitchen scale and it wouldn’t work until I dug out a USB-A -> C cable and plugged it into my desktop…

It just reminded me of how many devices like that I have. This scale, my wife’s sound torc, some car jumperstarters, and I think a one or two more…

I assume it’s because they just slap a usbc port on a dumb 5v circuit that doesn’t have a power negotiation controller. So the cable and the charger cant figure out the power needs of the device are and just never send any.

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 24 points 1 month ago (3 children)

But wait. Doesn't this make them both dumb? I'd expect a modern USB-C charger to still support basic 5v low current lazy devices too. If there's a USB-A to C cable that works, it must also still be possible to send the basic 5v down a C-C cable.

I also think there's always going to be a balance between how much a device needs to make and/or how much it needs fast charging to make sense to add the charging circuit for PD/PPS. Even $1-2 on top of the cost can ruin margins in the current electronic market.

[–] [email protected] 10 points 1 month ago

USB c has active negotiation for power and communication via a cc pin

The usb a to c cable has a pull up resistor that mimics this and says “give 5v”

Some usb c chargers have a fallback 5v mode for this scenario but not all do

load more comments (2 replies)