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The schematic bellow is a USB controller, designed to be used to change USB's VBUS voltage:

Question: Are CC1 and CC2 interchangeable, meaning that red-marked labels could be switched between them, i.e, is there any difference for the controller whether CC1 or CC2 are connected to the pins 10/11?

enter image description here

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    \$\begingroup\$ as far as I know, the whole purpose is to make it symmetrical. It will incorrectly understand if it's inserted "top side up" or "bottom side up", but if you don't care for that, and often you don't, you should be ok. But I'm not a usb expert. \$\endgroup\$
    – Ilya
    Commented Feb 9, 2021 at 14:22
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    \$\begingroup\$ I'm pretty sure it's irrelevant in USB PD applications. It will be relevant if the additional data pairs are used. Why do you want to switch them? To optimize PCB layout? \$\endgroup\$
    – Codo
    Commented Feb 9, 2021 at 14:23
  • \$\begingroup\$ @codo, exactly! It would be really good for the pcb layout. What you meant by additional data pairs? \$\endgroup\$
    – Emanuel M
    Commented Feb 9, 2021 at 17:49
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    \$\begingroup\$ The connector has four differential SuperSpeed data pairs, a pair consisting of the positive and negative line for the differential signal. Their use is negotiated the plug orientation matters. They are used for SuperSpeed USB and Alternate Mode (e.g. transmitting a video signal). \$\endgroup\$
    – Codo
    Commented Feb 9, 2021 at 19:01

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USB Type-C cables (and legacy cables) have only one CC wire. The wire indicates which Rx/Tx lanes to use. When connected, if CC1 is "active", it means "normal" plug, and the FUSB302 chip will inform the I2C host master over I2C interface about plug orientation (and port capability of the other side). Therefore the I2C host (your device) shall connect its USB3 data to Rx1/Tx1 lanes.

If CC2 is active, it will be the "flip" orientation, and your MCU should activate Rx2/Tx2 lane.

If you swap CC1 with CC2 on the FUSB302 inputs, the I2C registers will report inverse information. So you can do the swap, but you will need your MCU to invert a lot of information from the FUSB302 IC.

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  • \$\begingroup\$ Thanks. It is a complete answer, which gave me more ideas and technical base to understand USB-C design! \$\endgroup\$
    – Emanuel M
    Commented Feb 10, 2021 at 5:21

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