Can you please suggest me the solution for ground issue?

Discussion in 'General Electronics Chat' started by saidhi, Nov 19, 2015.

  1. saidhi

    Thread Starter New Member

    Nov 18, 2015
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    Hi All,
    Iam conncteing the two board grounds with a wire.If iam trying to connect other 3rd board ground to one of two boards,getting a large spikes on the ground and all the components which have connection with ground present in the two boards are affecting.
    So please suggest me know the solution is there any resiotor or any other component i need to connect for making the ground stable between the boards,so that to reduce the spikes on ground pin.
    Thanks in advance.
     
  2. #12

    Expert

    Nov 30, 2010
    16,298
    6,809
    Use longer wires so each board grounds at the same point (at the power supply).
     
  3. Lestraveled

    Well-Known Member

    May 19, 2014
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    A "star" grounding system works well. The grounds of all boards go to a common point. This common point is normally at the power supply.
     
  4. saidhi

    Thread Starter New Member

    Nov 18, 2015
    7
    0
    Thanks for reply,iam getting issue even longer thick wires are conencted.
     
  5. saidhi

    Thread Starter New Member

    Nov 18, 2015
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    0
    Thanks for reply,star grounding system works well ,but if the third board is any real time system (like any sources bd player,sinks tvs, oscilloscope ground).
    So in real time how to reslove this issue,is there any other solution like connecting capictor to ground through resistor between the grounds will work.pleas suggest me?
    Thanks
     
  6. Lestraveled

    Well-Known Member

    May 19, 2014
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    You are expecting too much from a grounding system. When your system frequency becomes very high, any grounding system becomes very weak. At very high speeds, differential communication, like LVDS, works very well.
     
  7. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Ensure a large decoupling capacitor on each board at the termination point of the conductors.
    Max.
     
  8. saidhi

    Thread Starter New Member

    Nov 18, 2015
    7
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    I tried all ,but still getting spikes on gnd pin.

    Thanks,
     
  9. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Is there more than one supply? Is any common connected to earth ground?
    Max.
     
  10. saidhi

    Thread Starter New Member

    Nov 18, 2015
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    yes we are connecting separate supplies and all are commonly connected to earth ground...
     
  11. MaxHeadRoom

    Expert

    Jul 18, 2013
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    What components are suspected of causing the spikes?
    It may require the addition of BEMF diodes and/or RC snubbers etc.
    Max.
     
  12. #12

    Expert

    Nov 30, 2010
    16,298
    6,809
    It's time for a drawing. All guesses are in. Now we need facts.
     
    PeterCoxSmith likes this.
  13. saidhi

    Thread Starter New Member

    Nov 18, 2015
    7
    0
    The components like
    LM2678SD-ADJ,nc7wz07 and nc7Wz17
     
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