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I am designing a USB hub circuit by using USB7002. It gives out two USB 3.2 Gen 1 ports with Type-C support. Each of these two ports has two pairs of RX and TX differential pairs (SS-RXA, SS-RXB, SS-TXA, SS-TXB). I am going to connect one of these ports to a Type-C connector. I know how to do it thanks to several evaluation board schematics I found (e.g.; EV33X03A).

But what happens if I want to connect one of these ports to a regular USB 3.0 connector (e.g.; USB1075-30-P-B) which does only have one pairs of RX and TX pins (SS-RX, SS-TX)? Is it possible to do such a connection? If yes, how do I do it?

Connection Diagram

simulate this circuit – Schematic created using CircuitLab

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Your schematics misses the CC1 and CC2 connections, the ones that determine the "polarity" of USB-C plug and engage (MUX) proper super-speed pair of signals. To connect the USB7002 USB-C port to a USB-A receptacle, you need to simulate proper CC signal and route the corresponding Rx-Tx pair to Type-A pins.

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  • \$\begingroup\$ This sounds about right. If the intention is to put a USB-A port on the output capable of USB-C then what needs to happen would be wiring it like a permanently attached USB-C to USB-A adapter/dongle. I recall there's three power output levels that can be specified but I'd have to look through the USB specs to refresh my memory. I believe the levels are 1.5A, 2.4A, and 3.0A but I'm likely mistaken. The example USB-A port is rated for 1.8A so that means wiring it up for the low power option. Again, I'm going from memory here so verify everything with the specs, don't trust my recollections. \$\endgroup\$
    – MacGuffin
    Commented Jan 16 at 8:52

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