Bests & Worsts Reviews from Amazon

Benson here again, reviewing legacy USB Type-C adapter on Amazon. Today I am reviewing CHENYANG's   "USB-C USB 3.1 Type C Female to USB 3.0 A Male Data Cable for Macbook Tablet Mobile Phone" This adapter does NOT comply with the USB Type-C specification version 1.1. The documentation can be found at usb.org under developers/usbtypec. The CHENYANG adapter violates Section 2.2 of the specification which states the following : "USB Type-C receptacle to USB legacy adapters are explicitly not defined or allowed. Such adapters would allow many invalid and potentially unsafe cable connections to be contructed by users." This is because if you combine this adapter with a USB Type-A to Type-C cable, you may create a dangerous condition where two power supplies may be connected together opposing each other using the combined cable. Furthermore, this adapter violates Section 2.3.1 : "Power is not applied to the USB Type-C host or hub receptacle (VBUS or VCONN) until the DFP detects the presence of an attached device (UFP) port." In my testing, even when no UFP device is attached, this receptacle port's VBUS line is powered on at 5V. It should only be at 5V when a UFP device is present. This adapter and port violates Section 4.5.1.2.1 - Please see figure 4-5. A correct DFP receptacle must use two distinct Rp resistors. According to my testing, the CHENYANG adapter leaves the CC lines completely floating, with no Rp at all on either CC pin. This means that the Chromebook Pixel 2015 does not detect a charger device at all, as it depends on the presence of Rp to start charging. Finally, this adapter also claims to support USB 3.1 SuperSpeed, but because it is only a passive adapter, there is no way to support both orientations of a potential USB device as that requires a mux on the receptacle end. Indeed, when I tried it, it would only ever enumerate a USB-C thumbdrive as high speed (usb 2.0). Long story short : This adapter is a type forbidden by the USB Type-C specification, and should NOT exist. It gets my lowest rating of 1-star because there is no simple thing that the manufacturer can do to make this adapter correct. As a consumer, DO NOT buy this cable to convert your USB-A chargers or USB-A hub or host ports.