Hi,
I am designing an FPGA board wit the DP83865DVH. On the RGMII side, there are single-ended signals.
The datasheet states that the Termination resistor should be Rs=Zo-Zout.
Zo = 50ohm controled impedance on the board.
Zout=35ohm according to page 73 of the datasheet. Which means the termination resistor should be 15ohm.
However, when I look at the AppNote AN-1408, the thermination resistor is 33ohm. What should I be using? 15ohm or 33ohm?
Thanks