I am trying to make PCB with W5500 (Ethernet module). I am not finding original supplies so I am looking for alternatives. I did research, and I couldn't find HH-1M1608-12 IJT. I looked at Sparkfun's designs and I found MH2029-300Y but when I read the data sheet they use different values.
Sparkfun uses the second photo. What I don't understand is how are they choosing right supplies. There is quite a difference. I know if they do that, there must be something. For example, I would choose this:
The L is using for here (right one Sparkfun's):
Is this L used for maximizing the power transfer, minimizing signal reflection from the load, or something that I don't know? Also, which L should I use (I don't have HH-1M1608-12 IJT)?