I have a USB C port on my computer and a USB C male-to-male cable, as well as USB C female and USB A 3.0 female breakout boards.

I have connected my computer to the breakout via USB C cable and wired the USB C breakout to the USB A breakout. So, I can connect devices to the USB A breakout to connect to my computer. The connections I used are below.

My problem is the CC1 and CC2 logic. I read about the pullup and pulldown networks needed for UFPs and DFPs for USB C. Some sources: (1), (2). So, I connected CC1 to a 5.1k resistor and connected that to ground. I did the same for CC2. This works when I plug in a USB 2.0 mouse (it uses D+ and D-) but this does not work for my USB 3.0 drive (even when I flip the cable).

1 -> A4,A9,B4,B9
2 -> A7
3 -> A6
4,7 -> A1,A12,B1,B12
5 -> B10
6 -> B11
8 -> A3
9 -> A2

Do I need a different resistor pullup/pulldown network in order for my design to work with USB 3.0?


1 Answer 1


If your A-to-C breakout does not have sufficient impedance control and other signal quality means to support Super-Speed signals (and even HS signals), your USB 3 drive won't work. And usually all commonly available C-C and A-C breakouts don't meet the necessary signal integrity requirements by long-long mile. Different CC logic won't fix this.


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