USB PD and Data transmission from two DFP ports to one UFP

[Ashtraywasp]

I want to design a USB4 Hub where one UFP USB C port has data connection and charging capabilities for a DFP, but can also get charge from a STUSB4710 that I'll supply with a DC voltage externally. So my hub would have a DC input and a USB C data I/O with DFP charging.

I'm fairly new to USB C design so I don't really know how I can manage CC from both the STUSB4710 and from the DFP USB C for simultaneous UFP charging and data transmission.

Any help would be appreciated.

[Peter BENSCH]

Welcome @Ashtraywasp, to the community!

The CC lines of USB-C PD (UCPD for short) have nothing to do with the data lines. In your case, the former are managed by the STUSB4710.

Hope that helps?

Regards
/Peter

[Ashtraywasp]

Thanks! I did consider that but I thought that the data port would need the CC lines for orientation detection, so unless I'm mistaken it'd need CC from the STUSB for PD negotiation and from the data port for orientation detection, and use something that can mux between the ports?

[Peter BENSCH]

Correct.

[Ashtraywasp]

What could I use to mux between the CC lines then? I assume it'll need management of some sort from an MCU, can I use a hub IC or is there an available IC that can do this without much configuration?