Hello,
I am designing a PCB with the DP83865.
Looking at the datasheet, it's not clear to me if the differential pairs from the magnetics to the DP83865 are strongly coupled or not.
In figure 18 of the datasheet says : '50-Ohm controlled impedance with respect to VDD or GND'
And in the tips below it says:
'Each MDI pair should be placed as close as possible in
parallel to minimmize EMI and crosstalk. Each member
of a pair should be matched in length to prevent mismatch
in delay that would cause common mode noise.'
So, looking at the terminations, I would imagine a line with 100 ohms differential impedance, with both lines coupled (this will cause the individual impedance being different from 50 ohms).
What is the correct configuration?
