The normal ethernet components configuration: MAC <-> PHY <-> Magnetics <-> RJ45. My RJ45 connector must be mounted on the system box's front panel, so there must be a wire routed from the PCB to the front panel connector. My system box contain many relays, so there may some interference from them. Now, I have several choices:
- Locate the magnetics at RJ45 connector side. And using CAT5 UTP wire to the main PCB. Then I can choose a RJ45 connector with integrated magnetics.
- Locate the magnetics at the PHY side, that is on the main PCB. Then use wires connect to the connector, which without integrated magnetics.
- If I can use two magnetics, one on main PCB, and one on the connector side?
Which method is better?
Best Answer
I would simply put an RJ45 MagJack on your circuit board right by the PHY. Then use an internal CAT5 cable to go to a panel connector. The panel connector could be one of these (although other options exist).
The above pictured connector is an inline coupler that permits Ethernet to pass through into an enclosure and maintain an IP67 rating.
If internal enclosure interference is an issue you simply use a shielded CAT5 type cable with the appropriate metal covered RJ45 plug ends. The above connector can be configured as a shielded unit on the inside with a shielded pigtail CAT5 cable.