Post #3289050
2026-06-07 17:22 UTC
@matildalove@wetdry.world @valpackett@social.treehouse.systems USB Power Delivery (USB-C) requires 5.1kΩ resistors to signal that the device wants 5V charging. Since these cost about a cent, many cheap devices don't have them, which causes compliant USB-C PD chargers to not charge them (USB-PD can deliver between 3.3 and 48V, depending on charger, and therefore needs some way for the device to inform it which voltages are supported; USB-A chargers don't have this problem – they always provide 5V, as devices predating USB-PD always expected 5V input, even if there were some proprietary standards that could provide more).
Replies (1)
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@endrift@social.treehouse.systems 2026-06-08 11:05
@jernej__s@infosec.exchange @matildalove@wetdry.world @valpackett@social.treehouse.systems mostly true, but one addendum: they cost way less than one cent (though a proper implementation requires two; one on each CC line). This is bottom of the barrel cheaping out, which makes it all the more disappointing when you find it on something that costs more than $5