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This USB Type-A to USB Type-C cable does not follow the USB specification; may cause damage to USB Hub, PC, or charger.
I'm a Software Engineer on the Chrome OS team at Google on the Chromebook Pixel and Pixel C teams. I recently purchased this USB 3.0 to Type-C Cable for testing.
I just wanted to follow up with you and let you know that these USB cables do not work properly with the Chromebook Pixel.
Upon closer inspection by our engineering team here, we have determined that your cable is not correctly following the USB Type C specification.
The specification can be found here :
[...]
Specifically, using this charging cable, the Chromebook Pixel will attempt to draw 3A of current over the cable, potentially damaging the USB hub or charger on the A side, which is not guaranteed to be rated at 3A.
Please see the document named "USB Type-C Specification Release 1.1.pdf"
section 4.5.3.2.4 for a description of why the Rp pullup is necessary.
Please see Section 4.11 and the following note :
1. For Rp when implemented in the USB Type-C plug on a USB Type-C to USB 3.1 Standard-A Cable
Assembly, a USB Type-C to USB 2.0 Standard-A Cable Assembly, a USB Type-C to USB 2.0 Micro-B
Receptacle Adapter Assembly or a USB Type-C captive cable connected to a USB host, a value of 56 kΩ
± 5% shall be used, in order to provide tolerance to IR drop on V BUS and GND in the cable assembly.
In other words, since you are creating a USB Type-C plug to a USB 2.0 Type-A Plug assembly, you must use a resistor of value 56kΩ. According to our testing, your cable uses a 10kΩ pull-up, which is not legal when the other end of the cable or adapter is a legacy Type-A or Type-B connector or receptacle.
Please let me know if there is any more information I can provide about why these adapters are problematic.
October 2015 · Industrial and Scientific · verified purchase