Hi Thomas:
This question relates to a comment you made in response to my earlier circuit design review request. In that post, you asked me to check if the terminations on the PHY side of the transformer were correct. At first thought I concluded my design was correct for the target PHY chip but would like your input.
The PHY chip I am using is the W5200 from WIZNet. The reference design shown below from WIZnet used a MAGjack type BS-R250210.
It has the same configuration as that specified by WIZnet for the symmetric transformer type shown in their data sheet below. The symmetric transformer design supports AUTO MDI/MDIX crossover.
I used the transformer type specified by TI in the EVM design as shown below in the circuit your just reviewed.
From my perspective, the Pulse H6062NL is a symmetric transformer design but has a tri-mode CM transformer on the PHY data side that interfaces with the port side transformer. I believe the Pulse transformer to be a suitable replacement that will support Auto MDI/MDIX with the manufacturer recommended termination on the PHY side as well as allow the DC voltage from the PSE to e recovered on the port side transformer center taps. . Do you agree?
Thanks,
Craig
