EMC queries

[chopper]

Hi everyone, cant anyone tell me what is the answer to the following questions? i have google and been reading but i cant get the answer for these question. Most of the website just tell how we should reduce emi by not telling the reason. Please do help me if you know .Thank you

1.Why interconnections between circuit groups should be minimised?

2.What would be the problem if interfering currents flow through ground conductor of sensitive circuits?

3.What would be the problem if interconnecting traces between two circuit groups traversed a third group?

4."All lead within a circuit group must be kept away from other groups, even if a longer lead is required" what does this statement implies ?

5. Circuit blocks should be arranged such that most interconnecting leads need not pass by a third type.

Why "most" instead of all?

 

[mneary]

Hi everyone, cant anyone tell me what is the answer to the following questions? i have google and been reading but i cant get the answer for these question. Most of the website just tell how we should reduce emi by not telling the reason. Please do help me if you know .Thank you

1.Why interconnections between circuit groups should be minimised? Because interconnections are more likely to emit and/or accept interference.

2.What would be the problem if interfering currents flow through ground conductor of sensitive circuits? In most designs, the assumption is made that the 'ground' potential is dependable. And since all current flowing through a conductor develops a voltage (even if small), this risk should be avoided.

3.What would be the problem if interconnecting traces between two circuit groups traversed a third group? The third group might induce unwanted signals into the interconnecting traces, and the traces might receive unwanted signals.

4."All lead within a circuit group must be kept away from other groups, even if a longer lead is required" what does this statement implies ? This is a corollary to (3).

5. Circuit blocks should be arranged such that most interconnecting leads need not pass by a third type. "most" instead of "all" because "all" is generally impossible.

Why "most" instead of all?

I hope that this has helped.

 

[RadioRon]

1.Why interconnections between circuit groups should be minimised?

2.What would be the problem if interfering currents flow through ground conductor of sensitive circuits?

3.What would be the problem if interconnecting traces between two circuit groups traversed a third group?

4."All lead within a circuit group must be kept away from other groups, even if a longer lead is required" what does this statement implies ?

5. Circuit blocks should be arranged such that most interconnecting leads need not pass by a third type.

Why "most" instead of all?

Perhaps these will help:

https://www.electro-tech-online.com/custompdfs/2009/12/szza009.pdf

Amazon.com: Introduction to Electromagnetic Compatibility (Wiley Series in Microwave and Optical Engineering) (9780471755005): Clayton R. Paul: Books


EMC for product designers - Google Books