Why large area of ground in PCB design can improve the performance of the PCB？

[zzllearner]

I allways be told that in order to achieve high performance of EMI&EMC, I should ensure the integrity of the grounding layer or large area of ground, would you please explain why it is? what thoery inside this?

 

[chuckey]

Re: Why large area of ground in PCB design can improve the performance of the PCB？

The ground should have a big area to stop series inductance in it down the length of the board. If the ground is big and close to conductors which are carrying high frequencies, the adjacent capacitance to ground will reduce the cross talk to other lines. The downside would be the rise/fall times will be slower.
Frank

 

[crutschow]

Re: Why large area of ground in PCB design can improve the performance of the PCB？

For proper circuit operation the ground should be at the same potential over the whole circuit, independent of any ground currents, but this is compromised by any ground impedance, and wires have relatively high resistance and inductance.
Having a ground plane minimizes this resistance and inductance, giving a low ground impedance.

 

[zzllearner]

Re: Why large area of ground in PCB design can improve the performance of the PCB？

Thank you so much.

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thank you very much.

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thank you very much.