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Amazon.com Now Bans USB Type-C Cables That Aren't Up To Spec (google.com)
Google engineer, Benson Leung has been on a mission to get rid of USB Type-C cables that aren't compliant with Type-C 1.1 spec. He reminds us that these cables could potentially lead to damage. Over the past few months, he has reviewed over a dozen of USB Type-C cables on Amazon.com and concluded that the vast majority of them aren't compliant with the aforementioned standard. Now he reports: Amazon.com has just made a change to their "Prohibited listings" for Electronics. They've added the following line: Any USB-C (or USB Type-C) cable or adapter product that is not compliant with standard specifications issued by "USB Implementers Forum Inc." What does this mean? It means that cable manufacturers who sell poorly made or intentionally deceptive USB Type-C cables and adapters are banned from Amazon, officially. Really great news, but we all have to continue to be vigilant and call out any bad products we find on Amazon and other stores (both online and brick and mortar) as we find them.
Now Amazon needs to deal with their entire counterfeit sex toy problem. If you're not aware, never buy sex toys off Amazon. Most of their products are low quality, counterfeits of more respectable brands. Often they're unsafe or made to low standards. Most manufactures will stop selling to any store that uses Amazon.
This is an important issue to me because I have devices that need good USB-C cables. If anyone else is in the same boat, here's a direct link to Benson Leung's reviews. Focus in on the 5-star ones and look for the value buys (if the product is still available):
https://www.amazon.com/gp/pdp/...
One of these cheap cables wasn't wired correctly and when Benson connected it to a Pixel C to charge some device (Nexus Phone?), the Pixel was destroyed. Apparently during manufacture two wires in one of the connectors were switched.
One difference between older USB cables is that the Type C cables contain a 56 k ohm pull up resistor for current control purpose. Some of the out of spec USB C cables with at least one USB Type C plug - probably a USB Type A plug at the other end - have a lower valued resistor and can cause problems. The problem is that if a lower resistance is used with a power supply that can only provide 1 Amp instead of 3 Amps at 5 Volts, the power supply can be fried as it tries to deliver 3 Amps. This could be the case for powered USB ports on computers. I've read that Apple laptops with a Type A compatible connector cannot deliver 3 Amps (1 Amp?) and might be at risk of damage when using an out of spec USB Type C connector cable with the wrong resistor. Further more, these out of spec cables may not be cheap. For more information, check the linked page and scroll down a bit:
http://www.androidauthority.co...
In a time of universal deceit, telling the truth is a revolutionary act. George Orwell
It's the port design on shitty (Intel, mainly) mobos. They're not individually fused (or fused at all).
The cable in question simply had the wrong pinout, and threw voltage onto lines that shouldn't have had that voltage.
You can't physically stop someone from applying potential to your exposed pins, but you can reasonably guard against it. Intel mobos typically don't (or didn't). All the brands people use for building their own (ASUS, GIGABYTE, ASRock, EVGA, MSI, Biostar, etc.) advertised USB (and other) short/spike/etc. protection as a feature years ago when it was becoming a frequent problem.
USB-C is designed to be able to deliver 100W DC (20A) - brains or not, swapped wires in such a cable is quite likely to be able to fry something. Lots of electronics aren't going to be able to survive up to 20A of current in a reversed polarity, or delivered on a pin that was supposed to be an outgoing signal or voltage.
In this case it sounds much simpler - and is a problem that could affect standard USB 2 and 3 cables as well: The wrong identifying resistor was included in a C-to-A adapter, making the device think it was plugged into a high-current power source, when the reality was that the USB C port was only able to deliver 2 amps. The resulting current draw then fried the USB port's power source, destroying the port and possibly the connected device.
A related problem is commonly responsible for slow charging with old-fashioned USB ports: The spec defines a 0.1A maximum current draw unless the device has negotiated for more. But having to talk to electronics makes for expensive wall-warts, so an auxiliary standard was created whereby the port could identify itself as a "dumb charger capable of delivering X amps" by including a ingle resistor, whose resistance was used to specify X within a few tiers, including tiers far in excess of what a "real" USB port can deliver (As I recall USB 2 ports are specced up to ~2A, assuming the connected device successfully negotiates for more than it's default 0.1A. Dumb chargers can be specced up to 5A with the right resistor) Some cables can interfere with that, generally resulting in well-behaved electronics "failing gracefully" and charging at a much slower pace
Not being versed in the intricacies of type--C lore, it sounds like what probably happened is that adapter cable *should* have identified itself as something like a normal low-current type-A port to connected devices, but instead delivered a garbage resistance that got interpreted as "take all the power you want", and the type-C port just couldn't handle the resulting load.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
The max current at any power level is 5A. The 100W spec is 5A at 20V.