TUSB8020B-Q1: Impact of GND offset on USB3.0 transmission

Hi TI team, 

  We have two PCB, ones is IVI PD charge(Max100W), the other is HUB-ECU(TUSB8020B),connected by 2m cable.

  1. When the PD charges 100W, the return of GND will raise the potential of  TUSB8020B GND (GND2>GND1). Will this affect USB3.0 communication?

  2. What is the Maximum allowable offeset of TUSB8020B?

  3.The line length is 2m. How to evaluate this risk

  thanks.