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A comment on 240W USB-C PD chargers are nearly here, says Framework CEO. Parent comment

Re:240W USB-C PD chargers are nearly here, says Framework CEO by TylerE on Friday June 09, 2023 @11:00AM (#36258837)
Because you have to size the cables based on amperage. The highest voltage supported by USB-PD is 20V. At 20V to deliver 240W you need 12 amps. That's already a fairly high number. At 300W you'd need 15 amps.

So unless you want to drag around an NEC type cable as thick as one of your fingers, you need to set a limit.

Edit: Fixed math. I haven't had caffeine yet.

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Re:240W USB-C PD chargers are nearly here, says Framework CEO by ScottKolo on Friday June 09, 2023 @11:14AM (#36259062)
While amperage is indeed a problem, PD 3.1 uses 48 volts to deliver 240W. https://www.usb.org/usb-charger-pd

That’s only 5 amps, but such a high-ish voltage is enough to lead to arcing. Charging cables are likely to require additional safety measures.

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Re:240W USB-C PD chargers are nearly here, says Framework CEO by delfinom on Friday June 09, 2023 @11:43AM (#36259540)
Not even safety requirements, going above 48V will start subjecting to your device to electrical code.
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Re:240W USB-C PD chargers are nearly here, says Framework CEO by f_devd on Friday June 09, 2023 @11:14AM (#36259069)
USB-PD now supports 28, 36V & 48V as well because of the higher wattage limit[0] (240/48=5A which is about what the cables are rated for I believe)

[0]: https://www.usb.org/usb-charger-pd

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Re:240W USB-C PD chargers are nearly here, says Framework CEO by kube-system on Friday June 09, 2023 @11:10AM (#36258993)
That was my first question -- is this still going to be at 20V? The kind of current that would draw is crazy for those tiny pins.

Looks like the spec goes up to 48v now:

https://en.wikipedia.org/wiki/USB_hardware#USB_Power_Deliver...

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Re:240W USB-C PD chargers are nearly here, says Framework CEO by parineum on Friday June 09, 2023 @11:14AM (#36259072)
It's 48V.
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Re:240W USB-C PD chargers are nearly here, says Framework CEO by edgineer on Friday June 09, 2023 @11:11AM (#36259008)
The 240W profile uses 48V
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