Beware of cheap USB Type-C cables, warns Google engineer

by: Robert TriggsNovember 5, 2015


The introduction of USB Type-C cables and devices is ushering in a new age of convenience, but it seems that not all cables are created equal. While it might be tempting to purchase a cheaper adapter cable to connect up your new gadgets, Google Engineer Benson Leung has been testing a few of them and has found that many aren’t actually suitable for use with his Chromebook Pixel laptop.

One of the important features with USB Type-C and 3.1 is support for 3A charging currents and this is where a number of budget cables are failing to match the standard’s specifications. Worryingly, this can be quite dangerous to hardware, as legacy devices may not be able to handle the charging currents when using adapter cables.

For example, when connecting up to an older USB 2.0 Micro-B charger with a Type-C adapter, the cable is supposed to provide a 56kΩ pull up resistor to the Vbus connector pin so that the host device correctly identifies the connected charger as a legacy device to lower the charging current to 1.5A or 2.4A. If you are using the USB cable for charging, the missing resistor could result in devices drawing more current from older chargers or hubs than they can handle, which clearly isn’t good.

Leung has found that a number of cables supplied on Amazon are missing this resistor or using 10kΩ instead, and therefore can’t charge up his Pixel laptop correctly. He has posted a series of reviews on a number of cables and also has instructions to help Pixel owners test their own cables.

If you’re concerned about this, your best bet is probably to stick with cables from reputable retailers. Adapters from FREiEQ, Belkin and iOrange all pass the test, or you can always use cables provided by your device manufacturer to ensure the correct support.

  • Toney B

    Considering I don’t have access to a test lab, how can I determine if my cables are acceptable? I purchased cables from Cable Matters, a vendor not reviewed by the Google engineer yet.

    • Josh

      Probably best to be safe than sorry and get one of the ones mentioned here. Not sure how much u paid but maybe u can get a refund.

  • flye

    Can someone port this to Android phones

  • Izzy

    What better way to see what are the good and crappy cables out there. I actually bought one of the cheap adapters he reviewed and glad I seen this post. Even though I’m planning on getting the Google coverage for my N6P, I don’t want the battery to suffer cuz I’m trying to save a few bucks on adapters lol.

  • k6tcher

    Unpopular opinion:
    Is this a problem with regular USB adapters that support fast charging? This USB – C stuff is way too infantile to become the mainstream. It needs to mature to become a replacement for regular USB. Still not there.

  • DustinDep .

    The problem is OnePlus were the first company to really push a USB Type C device, there cable actually has the exact same issue. Most of these companies based there design off of the OnePlus version since that’s the phone they were promoting them for. No damage will occur unless you have a faulty charger since there are fail safes built into all of those as well. The only items that will even try to pull 3A are the new nexus devices and the Pixel Range. Those devices would charge a lot slower with a USB A to USB C cable anyways so I don’t know why people would. These cables are still absolutely fine for data transfer, and they are in fact just like the OnePlus USB-C and Zuk Z1 USB C cable. Saying this I did contact a few of them and the only one that has gotten back so far was Orzly who said they already have new cables in production.

  • Bellamy wong

    I find this link can provide you the high quality USB-C cable. The cable I bought is very useful.