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Google Engineer Warns Against Perils of Buying Cheap, Third-Party USB-C Cables (hothardware.com)

MojoKid writes: A USB-C cable is just a cable. Or is it? Google engineer Benson Leung noted today that it's definitely not the case. Leung and his teammates at Google work inside of the Chromebook ecosystem, and as such, they've had lots of hands-on experience with USB-C cables. The Chromebook Pixel remains one of the very few notebooks on the market that directly supports USB-C. Nonetheless, in his experience, not all cables are built alike, and in some cases, cheap out-of-spec cables could potentially cause damage to your device. It's such a big problem, in fact, that Leung began buying cables off of Amazon and leaving his feedback on each one. Ultimately, what the problem boils down to is that some of the specifications in a cable may be not well controlled. He notes that in some bad cables, resistor values are incorrect, throwing off power specs wildly — 3A vs 2A in one example.

37 of 206 comments (clear)

  1. Just like HDMI cables by known_coward_69 · · Score: 5, Funny

    which is why i only buy Gold plated, oxygen free, twisted pair, sheathed Monster cables for $99.99 each. I can see the difference

    1. Re:Just like HDMI cables by Anonymous Coward · · Score: 4, Funny

      There is too much Ether in the cheap cables.

    2. Re:Just like HDMI cables by avandesande · · Score: 4, Interesting

      Having a cable format dependent on a resistor in the cable sounds like a poor design to me.
      ++ since it could damage hardware.

      --
      love is just extroverted narcissism
    3. Re: Just like HDMI cables by Anonymous Coward · · Score: 2, Informative

      You may not notice the quality difference with cheap analogue cables, but it is there. A bad quality digital cable will just not work, or be choppy as you noticed. That's why some say that cheap digital cables are okay, if it seems to work okay it likely is; that until they start becoming more than a cable.

    4. Re:Just like HDMI cables by Aaden42 · · Score: 4, Informative

      Using sense resistors in cables or charger plugs is pretty much universal and works very well. That's how phones tell the difference with between a "standard" 500mA USB port and a 2A high power charger. If the phone tried to draw 2A off a 500mA supply, odds are all the magic blue smoke would get out... (See http://blog.curioussystem.com/...)

      There's nothing wrong with sense resistors when the cables are manufactured properly. The problem is if the manufacturer puts the wrong resistors in because they don't know any better or because they're cheap and they're trying to cheat with cheaper components. In the case of USB 2 stuff, pulling 2A from a 500mA brick probably wouldn't end too well. For USB-C, if you try to pull 3A+ over a wire that's only rated for 500mAh... Well... Most likely what you've got there is a 3 meter long fuse... If you're lucky, the power supply will fail safely before the heat from the additional current ignites anything.

      Or more realistically, you may find the laptop gets flaky when it adjusts its power management to assume it can draw a particular amount of power from the cord only to fall short when power demands reach peak levels.

    5. Re:Just like HDMI cables by kaiser423 · · Score: 5, Informative

      USB type A to type C cables require a different pull-up resistor than the Type C to type C cables. Lots of vendors didn't do their due diligence and just put the USB-C spec'd pull up resistors in their A to C cables. As a result, devices try to draw too much power.

      I bought one of the bad cables, and was wondering why my wall charger was flaking out. Went online, and saw the issue -- my phone was trying to pull too much juice, overloading the charger and putting it into brownout mode. Now, this is a 4-port wall charger, so my other 3 connected devices were sitting there going charging/not charging/not charging at sub 1 second intervals for the ten minutes that it took me to figure it out. After that, my charger was acting really finicky, and I didn't trust it anymore after that current overload so I junked it. So, yea. Not overblown. Actual problem.

    6. Re: Just like HDMI cables by Anonymous Coward · · Score: 2, Insightful

      crazy things that just don't work

      You mean like the serial number that the USB specification forgot to mandate must be different in each device, so manufacturers just didn't bother and now operating systems have to treat plugging in the same device a second time as plugging in a brand new device because even though everything is identical, the device might not be?

    7. Re: Just like HDMI cables by Bing+Tsher+E · · Score: 2

      The power source should be doing that, never the cable. How does the cable know what type of voltage source it's plugged into? The cable should never have the resistors in it, the power source should.

    8. Re: Just like HDMI cables by Trongy · · Score: 4, Insightful

      How do you handle backwards compatibility with devices or chargers that can't follow the new communications protocol?

      Perhaps you think you are smarter than the engineers that designed USB-C and USB 3.1, but I do not.

    9. Re:Just like HDMI cables by davester666 · · Score: 2

      OMG. You mean I can get high by huffing really cheap ethernet cables. sweet!

      --
      Sleep your way to a whiter smile...date a dentist!
    10. Re: Just like HDMI cables by kqs · · Score: 2

      Also, if anyone thinks that idiot manufacturers (trying to save a few pennies) will screw up a simple resistor but will not screw up a chip, then I'm not sure what to say. A main reason we need smarts in the cables are because cheap chargers are not made with enough safety features or predate high-charge devices.

  2. Watch out for Bad Connectors Too by bill_mcgonigle · · Score: 4, Informative

    I bought a few packs of USB-C male and female connectors from China (to use for a non-USB application) and they were really junk. Looked like USB-C but the tolerances were terrible. Too soon for competitive quality forces to have kicked in, I suppose, but they didn't just make these bad connectors to annoy me - they must be out there in the wild too.

    --
    My God, it's Full of Source!
    OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    1. Re:Watch out for Bad Connectors Too by Richard+Dick+Head · · Score: 2

      Yep typical progression for China and why *all* USB 2.0 micro plugs are crap. Looks like USB-C is another casualty of the typical death-by-cheap process:

      1. Manufacturer cranks out millions of out-of-tolerance parts
      2. Manufacturer dumps them on the market for cheap to get rid of them
      3. Designers can't resist the shiny cheapness, design the faulty part in to their assembly
      4. Manufacturer gets order shock and starts cranking out parts again without any leeway to retool
      5. We have to replace our USB 2.0 micro cables every month because cheap defines the standard, not the spec

  3. Re:The legendary Chinese contempt for tolerances by gnupun · · Score: 4, Interesting

    Like health inspectors checking restaurants for bad food or procedures, isn't there an independent company that can randomly test and certify USB cables?

  4. Re:Why have they not tried this? by Firethorn · · Score: 3, Informative

    The answer to this is: They have. I'm sure that you'll find sources if you google.

    I'm not so sure about cables, but exploit devices have been found in usb chargers in airports.

    --
    I don't read AC A human right
  5. Re:Have to agree, same as HDMI1/2/3 by Anonymous Coward · · Score: 5, Insightful

    The problem is that the average Joe has no way to judge true quality at the time of purchase. It seems the best he can do is perhaps not buy the absolute cheapest. But what about one step up in price from that? Is that "good enough", or still junk? This is a basic flaw in capitalism: for it to work "best", the consumer must know what he is buying. In a world with unknowable and constantly changing suppliers for components, what was a "good" quality product one year could easily become "junk" next year.

    Known "quality" brands that cost more would seem to be the answer to this problem, but they face pressure to lower costs in order to increase profits, so this doesn't seem to be a permanent answer either...

    In the face of this, people just buy cheap, since they can't judge quality, hope it doesn't break, and when it does, just buy another cheap one. Explained in this link: https://en.wikipedia.org/wiki/The_Market_for_Lemons

  6. Waiting for the inevitable clusterf__k by ilsaloving · · Score: 3, Insightful

    USB-C could have been such an awesome standard. But when I read about all the possible feature variations (http://www.kitguru.net/desktop-pc/anton-shilov/not-all-usb-type-c-ports-are-equal-nine-implementations-of-usb-c-incoming/), I can only shake my head. While it's very cool, especially with integrated thunderbolt support, the idea of splitting it into different versions is just gonna cause nightmares.

    We're going to enter an age where people tear their hair out because everyone has the same port, but one person can do one thing with it but another person cannot. The whole HDMI versions confusion is gonna look tame compared to the confusion USB C will cause.

    1. Re:Waiting for the inevitable clusterf__k by ilsaloving · · Score: 2

      True... things were messy in the past, but at least you knew that, "Different connector, therefore different thing". A perfect example of what happens when that failed, was the whole 25-pin parallel vs SCSI connector. That was a lovely mess, up until IDE came about and wiped SCSI out of the consumer market.

      There is absolutely no reason why they had to repeat the confusion with USB-C & 3.1. They should have just said "USB-C = USB 3.1", and that was it. Throw in some adapters for compatibility, and we'd be done. But no, now we have to worry about USB-C v2.0, v3.0, v3.1, USB-C Thunderbolt....

      This means someone will be able to buy a USB-C monitor to connect to their USB-C laptop, and become frustrated that it doesn't work because they didn't realize that the USB-C on their laptop is only compatible with USB 2.0.

    2. Re:Waiting for the inevitable clusterf__k by tlhIngan · · Score: 2

      There is absolutely no reason why they had to repeat the confusion with USB-C & 3.1. They should have just said "USB-C = USB 3.1", and that was it. Throw in some adapters for compatibility, and we'd be done. But no, now we have to worry about USB-C v2.0, v3.0, v3.1, USB-C Thunderbolt....

      Those only matter if you use the auxiliary pins. If you're just using it as a straight up USB cable, any cable will do.

      The confusion happens if you want to plug in a device that use the auxiliary pins, and even then, there's a good chance devices will support multiple configurations.

      And Type C 2.0/3.0/3.1 only matters for data transfers - the cable and connectors are the same.

  7. Re:The legendary Chinese contempt for tolerances by Anonymous Coward · · Score: 2, Funny

    why is it that your libruls answer to everything is always more big government interference with jerb creators ?!!
    If people don't like getting salmonella poisoning, they'll post bad reviews on Yelp. Another win for the invisibul holy ghost hand of the market !!!

  8. I asked an expert by Anonymous Coward · · Score: 2, Funny

    I took a picture of my USB cable and showed it to an expert and he just said "I'll show you later". I don't get it.

  9. Benson is a pretty fantastic engineer by tlambert · · Score: 4, Informative

    Benson is a pretty fantastic engineer. He dots the i's and crosses the t's, which is somewhat rare these days.

    I hope Puneet (if Puneet is still his manager, as he was Benson's and mine, when I worked with Benson) is having Google pay for the cables he's buying, instead of Benson paying for them out of pocket.

    In any case, definitely take his Amazon reviews to heart: he knows what the hell he is doing, and he knows which end is the probe and which end goes in the meter. If he says a cable sucks, it sucks, and if he says it's good, it's good.

    1. Re:Benson is a pretty fantastic engineer by BitZtream · · Score: 2

      Yea, because Terry Lambert is a stranger that no one knows or trusts ... I mean, I've only known who he was without ever meeting him for the last 20 years ...

      https://www.linkedin.com/pub/t...

      Turn in your geek card karmawhore.

      --
      Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
  10. Why are resistors needed in a cable? by Fly+Swatter · · Score: 3, Insightful

    Seems to me that it would be a faulty design that requires a 'cable' to need any electronics at all.

    Just like anything with a jack, you can't really trust anything that may get plugged into it.

    Wires, wrapping, and shielding, sure. Electronics (caps, resistors, etc.) should be in the devices themselves, and devices when encountering bad cables should always fail 'safe'.

    1. Re:Why are resistors needed in a cable? by JediJorgie · · Score: 4, Informative

      yea, the problem is that they are not just cables, they are adapters. They adapt from USB-A to USB-C. As an adapter, they need the proper resister to tell the USB-C connected device how much power they can draw.

    2. Re:Why are resistors needed in a cable? by willy_me · · Score: 2

      And this helps how? Neither the device or host have knowledge of the cable that connects between them. Only by embedding this information into the cable can the two devices negotiate power settings that conform to the physical connection. The only alternative is to force active cables - such as Apple's lightning connector or Intel's thunderbolt connector. While this is not a horrible idea, it will not lead to low-cost cables.

    3. Re:Why are resistors needed in a cable? by thegarbz · · Score: 2

      Because the devices at either end have capabilities that can exceed some cables. A method for identification of cables is then required.

      This is really no different than wiring in the house, except that in your house the electrician needs to read up a code book to determine how to protect the cable at the time of installation. How many people will dig out a compatibility book before plugging USB device into USB device with USB cable just to make sure the smoke doesn't come out?

      We asked for this. We wanted the USB port to charge our phones in 30 seconds. Now we have to deal with the implications of such a request.

  11. usb 3 similar problems by divenpuke · · Score: 5, Interesting

    I worked on the first usb 3.0's for Apple. Same problem. We ended up buying nearly every different cable we could find and doing a tolerance study. Things varied so widely that the mouse i was using on my workstation was out of spec! The standards are CRAP. INTENTIONALLY. The mechanical tolerance standards read: for example the height of the internal spring contacts like 3mm max. no...minimum? pretty sure this thing ain't gonna work if the contacts don't...you know...touch anything. I had an internew w/ some asshat at Tyco - (they also make connectors) When i mentioned that the USB standards are crap, he said "oh yeah. we do that too. intentionally. We spend a lot of time developing the connectors to work properly and then because we HAVE to open source the standard, we'll obfuscate things such that we can gain a competitive advantage. Our cables and connectors work out of the box, or other companies are going to have to spend a couple months figuring things out w/ reliability testing before they can release a quality package. I about walked out of the interview at that point. Who signs their name to something that is intentionally a POS?? Speaking w/ the EE's at Apple, the signal integrity was written just as bad as the mechanical. Components of the signal integrity that would be controlled separately by the receptacle were lumped in with the cable. Just all junk. According to one guy Intel outsourced the design of the standard to india/china and just accepted the crap they gave them (because intel doesn't have like ... any mechanical engineers working there) J

  12. Re:The legendary Chinese contempt for tolerances by mrchaotica · · Score: 3, Interesting

    What's the difference between Joe's blog and Amazon.com customer reviews?

    --

    "[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz

  13. Re:Resistors in a cable? by flink · · Score: 4, Insightful

    Gods no. The important thing is that the cable be capable of carrying the current the device requests. If the resistors were just in the device, then it would have no idea if the cable you've used to connect it to the hub is thick enough to carry the current it is about to draw.

  14. not really fair by Xicor · · Score: 2

    well, we wouldnt have to buy third party cables if google actually gave us cables with the products we buy. i got myself a nexus 5x when it came out. it came with 1 3 ft usb-c to usb-c cable and no adapter to normal usb. i couldnt even plug the damned thing into my computer until the cables i ordered off amazon got here.

  15. Re:Monoprice? by amRadioHed · · Score: 2

    I mentioned them in a comment to this post yesterday:

    Benson Leung Yesterday 8:27 AM
    I have it on good authority that Monoprice's cables and accessories are compliant. I need to write a review though, maybe in a few days.

    --
    We hope your rules and wisdom choke you / Now we are one in everlasting peace
  16. Here's his list by godel_56 · · Score: 5, Informative

    Here's the list of cables that he tested, from the TFA. There are ten of them

    http://amzn.to/1MlG3g3

  17. Reminds me of the Prolific USB-serial converters by mykro76 · · Score: 2

    A decade or so ago the company I worked at had to repeatedly advise customers to use FTDI or Silicon Labs based USB-serial converters with our products. It got to the point that it was the first question on the tech support script. The cheaper converters based on Prolific chipsets were incredibly unreliable but customers kept buying them because on ebay one converter appears much the same as another.

  18. Re: Ah yes, a cable... by alcmena · · Score: 3, Insightful

    Actually, I think he's saying the person who can afford to work only 8 hours x 5 days is less tired and less likely to make mistakes than someone who must work 14 x 7. I don't think location had anything to do with his comment.

  19. Re:Reminds me of the Prolific USB-serial converter by Ol+Olsoc · · Score: 2

    A decade or so ago the company I worked at had to repeatedly advise customers to use FTDI or Silicon Labs based USB-serial converters with our products. It got to the point that it was the first question on the tech support script. The cheaper converters based on Prolific chipsets were incredibly unreliable but customers kept buying them because on ebay one converter appears much the same as another.

    There were a lot of counterfeit prolifics out there, so it isn't specifically a prolific problem. It's kind of like blaming Apple for the cheap fake iphone chargers.

    But yeah, if you can get a USB-Serial converter for 3 bucks, it might not be too good.

    I use FTDI mostly now, but have a few of the real prolifics setting around and in use. Including an ancient one that was used for a palm device, and still works in Linux even though Windows doesn't support it at all any more.

    --
    The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
  20. Re:The legendary Chinese contempt for tolerances by sjames · · Score: 2

    Name brands don't mean nearly as much as they used to.