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A comment on Hacking together a USB-C charger for a cheap Chromebook. Parent comment

Re:Hacking together a USB-C charger for a cheap Chromebook by bartvk on Monday October 12, 2020 @06:03AM (#24752923)
As far as I know, a USB-C charger should never have a hot V+/V- and that is what my beard trimmer requires. EDIT: alias_neo corrected me, and pointed out that it's D+/D- I'm thinking about.

On the other hand, this is expected behavior for a USB-A charger, and thus for a USB-A-to-C cable.

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Re:Hacking together a USB-C charger for a cheap Chromebook by fbrozovic on Monday October 12, 2020 @07:53AM (#24753470)
Your beard trimmer is likely missing the 5.1k resistors to GND on the CC pins, which enables the USB-C charger to output 5V. I had several devices (mostly flashlights with integrated battery chargers) that would only charge using A-C cables. After adding the resistors, C-C cables also work.
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Re:Hacking together a USB-C charger for a cheap Chromebook by bartvk on Monday October 12, 2020 @07:57AM (#24753498)
Probably, yes. I could do some soldering on the beard trimmer, but the electronics in the earbuds are positively microscopic.
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Re:Hacking together a USB-C charger for a cheap Chromebook by alias_neo on Monday October 12, 2020 @07:49AM (#24753454)
Perhaps you mean D+/D-? You won't get very far if V+/V- aren't supplying any current.
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Re:Hacking together a USB-C charger for a cheap Chromebook by cesarb on Monday October 12, 2020 @12:50PM (#24756438)
Actually, V+ (the correct name is Vbus) not supplying any current is the correct initial state for a USB-C socket. It instead provides a small current on each of the two CC pins (usually through a pull-up resistor on each pin), and only after it detects that the other side is drawing that current (usually through a 5.1kΩ resistor to GND on each pin) will it supply power on Vbus.
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Re:Hacking together a USB-C charger for a cheap Chromebook by bartvk on Monday October 12, 2020 @07:55AM (#24753487)
Yeah I think you're right! Updated my comment.
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Re:Hacking together a USB-C charger for a cheap Chromebook by pantalaimon on Monday October 12, 2020 @06:12AM (#24752964)
The USB-C Madness never seems to stop.
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Re:Hacking together a USB-C charger for a cheap Chromebook by auxym on Monday October 12, 2020 @07:39AM (#24753395)
Wait... How does it charge if it does not supply voltage?
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Re:Hacking together a USB-C charger for a cheap Chromebook by bartvk on Monday October 12, 2020 @07:54AM (#24753475)
Another poster on this same level provided the info! I made an error.
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