We are designing a device with a USB 3.0 Type C port. It is a pure UFP device, so no role changing.

But I got confused when trying to understand how much logic there is needed. On a lot of reference designs there is shown a data MUX on the superspeed lanes on both sides (host and device), and the data MUX is controlled based on the cable orientation, which can easily be found using the CC pins. But is a data MUX always necessary on the device side? Or can we just connect the device superspeed signals to USB Type C superspeed lanes1.


1 Answer 1


In simple words if your UFP is receptacle based you may need a MUX and if your UFP is plug based (like flash drive) you donot require MUX

  • \$\begingroup\$ Why is there a difference between receptacle and plug based ? \$\endgroup\$
    – JakobJ
    Oct 27, 2015 at 12:15
  • \$\begingroup\$ Aha, the plug is the UFP, where receptacle can be DFP/UFP... \$\endgroup\$
    – JakobJ
    Oct 27, 2015 at 12:48
  • \$\begingroup\$ If you'r device has a Type C receptacle it could be connected to USB 3.0 Type A port with a A-C cable. Without a MUX there is only 50% chance of plugging that in and getting USB 2.0 instead of 3.0 \$\endgroup\$ Mar 18, 2021 at 18:28

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.