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Ethernet Routing on non RJ-45 connector

Ethernet Routing on non RJ-45 connector

Ethernet Routing on non RJ-45 connector

(OP)
The project that I am work on has about 600 different signals coming out of a backplane to the fornt panel and I do not have too much room on the panel to put the regular Ethernet connectors. The operating environment demands circular connector (I know RJ45 are available in circular shell but I can not go that route). So my question is , Is it OK to use regular circular mil PCB mount connector for Gigabit(diff pairs) and 10/100base application? If yes, what will be the diff pin staggering (location) consideration?
Thanks

RE: Ethernet Routing on non RJ-45 connector

Done correctly, gigabit Ethernet can pass through (for example) 38999 type Milspec circular connectors with no noticeable effect. Obviously one chooses adjacent pins for each twisted pair. Less obviously and more difficult to manage during production, the twist should continue as close as practical to the pins. Use the correct and suitable cable. Keep an eye on backshell size versus total volume of cable. Beware wiring errors.

Each of the four pairs carries 250 Mbps, so maintaining good wiring practices (RF!) will allow a successful Gb connection.

RE: Ethernet Routing on non RJ-45 connector

You were asking about the PCB mounted connector. Some of my response is only applicable to the wired cable side of the connection.
 

RE: Ethernet Routing on non RJ-45 connector

(OP)
PCB pins are available for regular mil 38999 connectors but the maximum pins I have seen on them so far from Amphenol are 128. Little less for my application. I will keep looking. You do not think impedance mismatch at the contacts will  be a problem? But again that will be a problem with RJ 45 also to some extent. Do I need to separate the pairs A,B/ C,D with chassis gnd or circuit Gnd? I think that might help in reducing crosstalk.
Thanks for a  professional response. I am glad there is less student stuff on this forum. Student type responses are big drag when sharing professional experience.  

RE: Ethernet Routing on non RJ-45 connector

Harting's HAN series of modular connectors can probably get close to the pin count you require. VE1BLL's comments would apply there also.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: Ethernet Routing on non RJ-45 connector

Kep,

Students are not allowed to post on these fora, only practicing professionals (some not currently practicing, and some not quite professional winky smile)... you'll receive a higher grade of answer here.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Ethernet Routing on non RJ-45 connector

One important fact to keep in mind is that you're not the first to contemplate running Gb Ethernet through military circular connectors. Many modern mission systems rely upon Ethernet (including Gb Ethernet) and virtually all that equipment, from video encoders to routers and switches to processors to recorders, they all use 38999 or similar Mil-Spec circular connectors.

If you're designing such equipment yourself, then you certainly need to be concerned about the possibility of an impedance bump at the connector, but if you make reasonable efforts to minimize it, then there shouldn't be any problem.

We can discuss the details if you wish.

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