Bests & Worsts Reviews from Amazon

UPDATED (11/20/2015): TechMatte has been extremely responsive to my inquiry in the last month. They've contacted me and let me know that they were in the process of fixing their cables. They were also kind enough to send me an early engineering sample of the fixed cables one week ago. This re-review of their Micro-B to C adapter is not of the engineering sample, but of the real production version that I purchased again from Amazon three days ago. Let's get started on the spec compliance test. Once again, my test device is a Chromebook Pixel 2015. I am using a Chromium Twinkie USB PD sniffer/debug device, available here : Plugable USB 3.1 Type-C (USB-C) Power Delivery Sniffer I have plugged in the TechMatte adapter to a USB Type-A to Micro-B cable that came with my Motorola Nexus 6 phone. It is plugged into the following 10W charger : Dell 10W Adapter Spare Wall Charger for Venue 8 Pro/8/7 (XDN34) The charger, the cable, and the adapter are plugged into Twinkie, which is acting as a passthrough to Pixel. Picture attached. Let's run the ectool command from Pixel: localhost ~ # ectool --name=cros_pd usbpdpower Port 0: SNK Charger DCP 4656mV / 1872mA, max 5000mV / 1872mA / 9360mW Port 1: SRC So far so good. Pixel is charging at almost 1.9A from the 2A Dell charger. It's correctly identifying as a DCP charger. Let's check Twinkie: > adc CC1_PD = 417 CC2_PD = 15 The ADC command reads the current voltage values from the CC pins. As you can see here, CC1_PD pin has a value of 417mV. Referring to the USB Type-C Specification Table 4-25 Voltage on Sink CC pins, this voltage falls right in the middle of the range allowed for vRd-USB, meaning that yes, this cable has the correct 56kΩ pullup resistor! Other subjective consideration : The adapter is nice and small, perfect for slapping on your most used USB micro-b cables. It's tiny, barely wider than the Type-C plug or Type-B receptacle. Very compact design. In conclusion : The TechMatte adapter has been updated to fully support Chromebook Pixel and other Type-C devices that depend on correct CC termination! It is now officially futureproof for the Type-C generation and gets my full recommendation. I recommend this for anyone with a USB Type-C phone like Nexus 6P/5X or Pixel device. TechMatte as a company has been very responsive and they've gone to great lengths to follow my advice at every stage. Thank you, TechMatte! ORIGINAL REVIEW (10/29/2015): I'm a Software Engineer on the Chrome OS team at Google on the Chromebook Pixel and Pixel C teams. I bought these two USB-C to Micro USB adapters from TechMatte and found they do not work properly with the Chromebook Pixel. Upon closer inspection by our engineering team here, we have determined that this adapter is not correctly following the USB Type C specification. The specification can be found here : http://www.usb.org/developers/docs/usb_31_102015.zip Specifically, these adapters do not charge the Chromebook Pixel 2015 because the adapters leave the C-C lines floating, where the specification requires a Rp pullup to Vbus to identify the cable as a legacy adapter or cable. 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 also 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 k' ± 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 Micro-B receptacle assembly, you must use a resistor of value 56k' as a pullup to Vbus. This cable does not do this. Please let me know if there is any more information I can provide about why these adapters are problematic. If you are a consumer looking for a cable that is compatible with Pixel, do not use this one.