PCIE Repeater DS80PCI800

Dears,

Could you help to clarify below why DS80PCI800 spec has defined x8/x16 pcie Gen 1/2/3 supporting, but it also defines 8 channel PCie for this part?  Thanks

DS80PCI800：x8/x16 PCIE Gen 1/2/3 means that it could realize x8/x16 PCIE with two or four DS80PCI800 pcs。

Due to we’re using“DS80PCI800 “ repeater design in our PCIE interface. there  are two questions as below

1. Could you help to explain why DS80PCI800 chip need to be closing at RX side pin?

2. 

3. could you also help to provide simulation module of DS80PCI800 for us.

1. The DS80PCI800 is input equalization, and an output de-emphasis driver.Due to the greater strength of the EQ compared to the De-emphasis driver, we recommend it placed closed to the RX side not the TX side. This placement gives the PCIe preset distance to attenuate and the possibility of over-equalizing the signal is greatly reduced.

2. There is no simulation model of DS80PCI800, but recommend using WENENCH for design and simulation. 

http://www.ti.com/product/DS80PCI800/toolssoftware