this post was submitted on 10 Aug 2024
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USB-C can deliver more power which is why they've been appearing more and more on charging bricks.
I had to look up, USB PD does work with a USB A port.
That being said, I personally want to get to a single type of cable so any I get can be spares for anything I have, so I like USB c to be all around.
That ALSO being said, I doubt I will ever get to all USB C.
Side note, USB PD is awesome because I know it can do up to 240w. (Last I knew.) That is 48v at 5a, so I am not sure what they can do to squeeze out more wattage.
USB PD is not specced for USB-A which is limited to 5V 2.4A. They had Quick Charge back in the day that got a little bit higher power using 9V but all the modern higher voltage high current PD stuff uses USB-C. The USB-A cables aren't specced to be running 5A or more that PD uses.
https://www.usb.org/usb-charger-pd
C-C carries more power than A-C?
USB-PD is only specified for USB-C. I think they use an extra channel for this configuration, so it's not possible to use PD over A plugs.
There were competing standards like Qualcom quick charge. AFAIK they never went above 20-ish watts on USB-A, while PD is specced at up to 240W.
Interesting. I always figured the wires inside were all the same.
Oh no the wires are a mess. Usb3 cables have extra wires and pins for super-speed. IIRC usb-c has said extra pins for usb configuration like pd or displayport alt mode. The wires can also be different. Some can carry more current, most cables are insufficient for really high data rates...
Yes, USB-A is only spec’ed for 5v 2.4a, so it will end up throttling the USB-C end which has higher power delivery specs.