5 ms·

I ordered one of these $2 USB 3 Type-C to USB 3 Type-A cables from eBay so I could transfer files from my Nexus 5X to my MacBook. Since these stories started po

I ordered one of these $2 USB 3 Type-C to USB 3 Type-A cables from eBay so I could transfer files from my Nexus 5X to my MacBook. Since these stories started popping up I just placed it in a drawer. It has no wall socket adapter and I wonder if it's safe to use for the phone if I just connect it to the computer. Seems the computer USB port shouldn't be able to feed enough power to hurt the phone. True?

ploxiln 11y ago
In this case, the problem is not how much power the computer "feeds" to the phone, the problem is how much amperage the phone draws from the computer. The bad Type-C cable can be incorrectly configured to indicate to the phone that the Type-A computer end can provide more amps than it actually can, and then the phone will provide less effective resistance across the 5v power wires than is appropriate. In this case it's more likely to damage the USB port on the computer. It's also theoretically possible that this cheap cable could be wired very wrong and short some power wires itself. But there was, like, only one cable people have found on amazon that was that ridiculous ...
jeeva 11y ago
False, possibly: https://www.amazon.com/review/R2XDBFUD9CTN2R/ref=cm_cr_rdp_perm https://www.amazon.com/review/R2XDBFUD9CTN2R/ref=cm_cr_rdp_p...
bipson 11y ago
IIRC its the other way round: your phone will not realize it is actually being plugged into a USB Type-A port, which might not be able to (safely) supply the current a USB 3 Type-C port potentially would allow. This is done by terminating a certain pin of the cable with a respective resistor, while USB Type A has no such pin and such a cable must thus by default terminate to 56kOhm. If now the cable does _not_ terminate, the phone might think it can draw way more power than the PCs slot can safely deliver, thus frying your PC port. The phone is not the problem.

ploxiln 11y ago

In this case, the problem is not how much power the computer "feeds" to the phone, the problem is how much amperage the phone draws from the computer. The bad Type-C cable can be incorrectly configured to indicate to the phone that the Type-A computer end can provide more amps than it actually can, and then the phone will provide less effective resistance across the 5v power wires than is appropriate. In this case it's more likely to damage the USB port on the computer. It's also theoretically possible that this cheap cable could be wired very wrong and short some power wires itself. But there was, like, only one cable people have found on amazon that was that ridiculous ...

jeeva 11y ago

False, possibly: https://www.amazon.com/review/R2XDBFUD9CTN2R/ref=cm_cr_rdp_perm https://www.amazon.com/review/R2XDBFUD9CTN2R/ref=cm_cr_rdp_p...

bipson 11y ago

IIRC its the other way round: your phone will not realize it is actually being plugged into a USB Type-A port, which might not be able to (safely) supply the current a USB 3 Type-C port potentially would allow. This is done by terminating a certain pin of the cable with a respective resistor, while USB Type A has no such pin and such a cable must thus by default terminate to 56kOhm. If now the cable does _not_ terminate, the phone might think it can draw way more power than the PCs slot can safely deliver, thus frying your PC port. The phone is not the problem.