Tag Archives: vbus

因為一條 USB 線燒了三個設備...

Benson Leung 花了不少時間在測試 USB 線 (「Google 工程師在 Amazon 上留下對 USB-C 線的精彩評價...」與「Google 工程師在 Amazon 上對 Type C USB 線的評論」),而前陣子他測到一條超棒的 USB 線,把他三個測試設備都燒壞了:(出自這邊)

Surjtech's A-to-C cable seriously damaged a Pixel 2 laptop and two USB PD analyzers.

他在 Amazon 上留下的說明可以看到他發現廠商直接把 GND 與 Vbus 的線接錯了 (這個有厲害...):

I directly analyzed the Surjtech cable using a Type-C breakout board and a multimeter, and it appears that they completely miswired the cable. The GND pin on the Type-A plug is tied to the Vbus pins on the Type-C plug. The Vbus pin on the Type-A plug is tied to GND on the Type-C plug.


I've had the cable taken apart, and we've discovered some interesting details. I'll post a post with pictures soon.

1) Vbus and Gnd are switched. Red wire goes to G on the Type-C's PCB, Black wire goes to V.
2) 10 kΩ resistor instead of 56 kΩ resistor used.
3) resistor hooked up as a Pull-down instead of a pull-up
4) Wire is COMPLETELY missing SuperSpeed wires. It is NOT actually a USB 3.1 cable, even though it has a blue connector on the A side and SuperSpeed logos.

Bad. So bad.

照片可以在這邊看到。看起來 Benson Leung 得再去 Google 內要新的機器來測試了...