TDA4VH-Q1: PCIe signal and connector impedance

How about question #1 and #2? 

What is the impedance used on the EVM board for PCIe signal?

The EVM is routed with 100-ohm clock and 85-ohms PCIe signals.

Then didn't consider the connector's impedance compliant?

Not sure I understand your question.  I've stated the PCIe spec has a range for the REFCLK impedance, which covers both 85-ohms and 100-ohms.  REFCLK does not operate at same rate as the PCIe data, and thus is the reason for the relaxation. 

In your design, you can route REFCLK at 85-ohms to match connector if you wish.  That would be within the PCIe guidelines.

Thank u.  

Dear expert:

#1、I want to make sure that TDA4VH's SERDES-REF-CLK  diff-input impedance . Are both 85-ohms &100-ohms OK for TDA4VH？ 

#2、 SERDES-REF-CLK INPUT ， is that LPHSCL voltage ok for TDA4VH？

TDA4VH's SERDES REFCLK are routed at 100-ohms differential on our EVMs.  This is also how TI tested.  As previously mentioned - I think both impedances are within the standard's specification, but I recommend following our EVM/tested systems.  Here is some additional information on PCIe routing - again suggesting 100-ohms.  www.ti.com/.../snla426.pdf

I'm checking on the REFCLK input specifications.

Sorry for delay.  Still waiting on REFCLK input specifications.

OK  thank u. You check on  your early post :https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1062475/tda4vm-tda4-serdes-refclk

Yes - the linked E2E provides the voltage threshold information I was requesting. 

But it is still not clear that TDA4VH'S SERDES REFCLK's type.    Can it be LPHCSL ,which don't nedd 50 ohm to gnd?

I think this is answered in the linked E2E thread.  The TDA4VH's REFCLK input type is HCSL. Yes - LPHCSL driver should be compatible with TDA's clock receiver.