Post #3289054
2026-06-07 17:32 UTC
@matildalove@wetdry.world @valpackett@social.treehouse.systems many cheap sources just give you 5V with no particular current limit - just whatever the supply can handle until the voltage sags out of spec or something overheats. they don't bother looking for the 5.1kΩ resistors. this generally just works because the supply can handle at least 5V 1.5A, so it doesn't matter if the resistors are present or not, and if the device tries to actively handshake for higher voltage/current it detects that the source doesn't support it.
Replies (1)
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@gsuberland@chaos.social 2026-06-07 17:34
@matildalove@wetdry.world @valpackett@social.treehouse.systems however, this causes a problem: if a device manufacturer *assumes* that the source is one of these noncompliant ones that just lets you draw 1.5A no matter what, then they can save a few fractions of a penny per unit by not including the resistors! unfortunately when you plug the device into a USB PD compliant source it *does* check for the (missing) resistors and won't give any power.