Hi,

Can I place ethernet lines (MDIA+,MDIA-,MDIB+...) on a PCB?
I want to design a board that has two RJ-45, without a PHY component. Do i need to use isolated coils? do i need to consider impedance matching?

Thankyou,
Danna

 

If you mean you want to connect two RJ45 devices in parallel you can only do this if one does not respond to signals eg for a monitor scope connection.

If you mean you want to provide two separate RJ45 connections via IP by using the redundant lines in an ehternet cable you can do this.

go well

 

you didn'y understand me.
I want to connect a cable to a board with RJ-45, pass ethernet lines through the board (without using them) and connect them through another connector (NOT RJ-45).

thank you,
Danna

 

I'm still new at all this, but I don't understand what your asking either

 

has two RJ-45

Of course I didn't understand you. You specified two RJ45, now you say there is only one.

Make up your mind.

 

CAT-5 uses four twisted pairs so that noise will be cancelled out.

If you're going to route the signals across a board, you'll need to ensure that you won't get coupling between other pairs. You might run a ground strip between them to provide a barrier.