Dear TI,
we need technical support to solve an issue with an USB3.0 bus that use TUSB501 devices. We developed a carrier board with a Q7 module. The USB3.0 path include a 2:1 mux, TUSB501 redriver, common mode choke, ESD diode and finally an USB3.0 type-A connector.
Due to an error during developing phase we have chosed a wrong common-mode choke (WE-744212331) for the two SS pairs (SSTX and SSRX).
This common mode choke have a very large footprint compared to a standard USB3.0 choke. I tried to short circuit the pads of the choke on the PCB but nothing work. I think that this large footprint cause a signal integrity problem but we have no instrumentations to check this.
So we need support to verify if at least the electrical schematic is correct and if we can do something to make PCB working.
We have another problem about simulation in the Hyperlynx software of this USB3.0 path. I tried to make a SI analysis on the SSTX pairs from Q7 connector to the USB type A connector. While i'm seeing the correct input signal on the TUSB501 i can't see nothing at its output. I opened a thread days ago on this forum about the problem: e2e.ti.com/.../2362093
I modeled the SSTX Q7 pins using the TUSB501 IBIS model (i use the Tx_p and Tx_n outputs), the 2:1 mux is modeled by its on-resistance, the TUSB is modeled by its IBIS model, the chocke is modeled as 0ohm resistor, the ESD diode is modeled by its equivalent capacitance and finally the USB connector is modeled using Rx_p and Rx_n inputs of the TUSB501 IBIS model.
Does this modelization is correct?
I attached all the infos.TUSB501.zip
Thanks very much for your support
Best Regards
Nick
