RJ45 PCB Layout help

Discussion in 'General Electronics Chat' started by RodneyB, Jul 20, 2015.

  1. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    I want to join 2 x RJ45 sockets in parallel on a PCB. I use proteus 8 professional and not for the life of me can I do a single sided PCB layout. I have even tried the auto router and it fails.

    Any help will be greatly accepted.
     
  2. BReeves

    Member

    Nov 24, 2012
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    So you want to have two PC board mount RJ-45's sitting side by side wired in parallel on a single sided PC board? Can't be done without jumpers. If I was on my other computer I could do it real quick with Express PCB.
     
  3. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    Ok I never considered jumpers I will try it now
     
  4. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    It can be done easily with an S shaped routing between the two connectors. For two connectors at the right edge of the board, facing to the right (outward):

    8 traces go in parallel to the 8 pins of the upper connector.
    The 8 traces continue straight under the connector body, then all 8 turn 90 degrees to the right to head downward.
    When they are even with the gap between the two connectors, hen they turn 90 degrees to the right to head back between the connectors toward the inside of the board.
    Once past the back of the connectors, they turn 90 degrees left to go down behind the lower connector.
    Then they turn 90 degrees left again and go straight to the 8 pins under the lower connector.

    No jumpers, and equal average path length for all 8 signals.

    ak
     
  5. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    Even with Jumpers I have failed
     
  6. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    I am struggling to follow this explanation. Would you be good enough to post a sketch.

    Thank you
     
  7. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Rodney,
    Can you post a sketch of the desired orientation of the 2 jacks on the board?
    We don't know if they are next to each other, opposing each other, one on one side and one on the other,etc...
    Could be as simple as this..

    parallelrj45.PNG
     
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  8. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
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    This is one of several solutions:
    upload_2015-7-20_16-22-40.png

    John
     
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  9. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    In addition to seeing how you intend to place them on the board we clearly need to know if they are through hole or surface mount type.. ;)
    Post the part number/datasheet
     
  10. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    Single sided layout. Traces extend outside the lower connector for clarity. All traces between the two connectors are the same length.

    ak
    RJ45-SS.gif
     
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  11. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    Is this for ethernet? If so, you really should keept the impedances correct, so using pairs from a CAT5 cable and short traces just to join the wires would be advisable.
    Also if this is for 10/100Mbit ethernet then you likely need just four wires.
     
  12. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    Sorry I don't have a part number But I have attached Photos of the socket. They are through hole mount I want to have them side by side
     
  13. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    I am extending my Internet Cable to a router, My cable is 10 meters short so I just want to make a link with the sockets
     
  14. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    Thank you I will follow this example. The tracks are going to be very thin.
     
  15. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
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    If available at your location, a simple coupler like this is cheap ($2.98 USD):

    upload_2015-7-22_13-2-9.png

    Home Depot carries them in the US.

    John
     
  16. RodneyB

    Thread Starter Active Member

    Apr 28, 2012
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    Thank you. In Zimbabwe there is no Chance I would find one here
     
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