TUSB1046A-DCI: Display port or USB2 FTDI periperal on USBC

David Bleakley

Part Number: TUSB1046A-DCI
Other Parts Discussed in Thread: TS3USB221, TPS65987

Normally USB-C in Alt mode would Have the USB2, USB SS and Display Port from the Host, in this case, a COMe board.

I have a USB-C Connector that we would like to use as a Display Port output from a COMe or as a connection to a USB 2.0 FTDI Peripheral. Both do not need to be active at the same time. Is this possible?

Is the TUSB1046A is ok without a USB SS connection?

If it does need USB SS is the circuit ok without the corresponding USB 2.0 from the COMe?

I could add a USB2.0 Mux if needed to switch between FTDI USB2.0 and COMe USB 2.0.

over 3 years ago

0 Malik Barton57 over 3 years ago

TI__Guru 64326 points

Hi,

TUSB1046A does not need USB 3 SS connection to remain functional. Typically if the USB-C connector is a DP host the SUB 2 connection is connected to the USB 2 Host controller not USB 2.0 PC. Is "COMe USB 2.0" a host or device? When is the FTDI USB2.0 needed?

0 David Bleakley over 3 years ago in reply to Malik Barton57

Prodigy 180 points

Thanks so much for your reply.

COMe is the main host CPU PCB potentially providing USB 2.0 /SS and DP.

The idea would be that in normal circumstances a user could use the USBC socket for Display Port. The FTDI will provide debug UART terminals for development only.

The ideal would be to use the display port and the FTDI USB 2.0 concurrently during development, but I don't know if this is possible.

0 Malik Barton57 over 3 years ago in reply to David Bleakley

TI__Guru 64326 points

Hi David,

In the final product the FTDI should not be connected and COMe USB 2 pins should connect to the USB-C connector during normal operation and compliance testing. Looks like you will need a USB 2 mux here, check TS3USB221. Since the FTDI part is only needed for development purposes perhaps a jumper option could work here.

0 David Bleakley over 3 years ago in reply to Malik Barton57

Prodigy 180 points

Hi Malik,

Thanks for your reply. I had been looking at the TS3USB221 and have been considering using the TPS65987 to control the mux. I will review this with the team.

0 Malik Barton57 over 3 years ago in reply to David Bleakley

TI__Guru 64326 points

Sounds good, let me know if you need anymore information.

0 David Bleakley over 3 years ago in reply to David Bleakley

Prodigy 180 points

Hi Makik,

We have decided not to disconnect the SS USB from the TUSB1046A. Can these be left floating?

+1 Malik Barton57 over 3 years ago in reply to David Bleakley

TI__Guru 64326 points

Hi,

TUSB1046A SSTX and SSRX pins can be left floating.

Because of the Thanksgiving holiday in the U.S., TI E2E™ design support forum responses may be delayed from November 25 through December 2. Thank you for your patience.

Interface

Interface forum

TUSB1046A-DCI: Display port or USB2 FTDI periperal on USBC