Hi,
From the IBIS model for TPS65921 for ULPI there are three model selector options available they are digio_50_50ohms, digio50_50ohms_pd, digio50_50ohms_pu.
PD and PU talks about pull up and pull down models. The other model "digio_50_50ohms" is an I/O model with PU and PD disabled. What does 50 ohms here refers to?
Kindly clarifiy.