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2 wires side by side, Can they reduce the Electrical effect on another component?

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epilot

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Hello folks,

Please, I have a question...

Suppose that I have an Electronics components, it can be a resistor or anything else, and it might be created inside a chip if you like. The design is somehow that I have to pass a wire which is connected to a potential across the component (from the upper or under the component).

Now the question:
Do you think that I can put another wire in parallel to the side wire (side by side) so that I reduce the "Electrical" and Electrostatic effects of the wire on the component.

Note: The magnetically effect of the wire(s) on the component is not important for me.

Thanks.

P.S. One way is to shield the component by putting a grounded conductor between it and the side wire. But I am going to do it by using a second wire if possible....
 
Using a shielded wire would be most effective. Second best would be a twisted pair with one wire grounded.
 
What kind of voltage and or frequency is in that wire that you are worried about the produced electric field?
 
Now the question:
Do you think that I can put another wire in parallel to the side wire (side by side) so that I reduce the "Electrical" and Electrostatic effects of the wire on the component.
It most likely would have little or no effect unless the second wire carries a signal that is equal and opposite to that of the first wire (e.g., the two wires carry logic signals that are logical complements of one another, or the two outputs of a differential-output amplifier in the case of analog circuitry), and the two wires were very close together compared to their distance from the component. Even then, I doubt that you would achieve significant cancellation of the interfering signal.

Are you really sure you actually need to take any corrective measures here?

You probably would, if the component in question is connected to a circuit node (or nodes) that has a very high impedance (for example, a high-value resistor connected to an opamp input) and is part of a circuit which processes low-level signals with substantial bandwidth, AND the wire running under the component is carrying a high voltage (logic level or higher) signal with a lot of high-frequency content.

But otherwise, you may not have an interference problem, and corrective action would be unnecessary.
 
you sound like you are talking about worrying over the E field rather than the B field.

So you are right, having both go and return wires together will not help with E field disturbances....because what you are doing by having go and retun wires together, is reducing the loop area of the current loop, and thereby reducing the B field due to the "Loop " antenna...so if youwant to reduce E field disturbance , then you must put some damping in there to reduce the dv/dt of the signal in that wire of yours.
 
can you define ?
- the interfering signal? slew rate ? for voltage & current?
- the affected channel? Signal , impedance?
- the proximity distance and length between interference (noise) and signal
- any present measurements? desired immunity or SNR?
- application?
 
I guess this is an academic question.

Each current carrying wire generates an EM field which generally reduces in amplitude with square of distance unless there are reflections.

It is possible to cancel near field with an opposing current wire placed so the fields are symmetrically cancelled and wires very close to each other relative to the gap to the component.. This is called differential mode and is reliable method to reduce interference. Often the pair is twisted for better radial symmetry.

When conductors are planar and cannot be twisted such as on a PCB, then differential tracks with ground tracks on either side and between or above and below are often used. This differential method is useful for ingress and egress noise cancellation and if the return is ground can be done with single ended tracks with suitable grounding methods.
 
Last edited:
Hello folks,

Please, I have a question...

Suppose that I have an Electronics components, it can be a resistor or anything else, and it might be created inside a chip if you like. The design is somehow that I have to pass a wire which is connected to a potential across the component (from the upper or under the component).

Now the question:
Do you think that I can put another wire in parallel to the side wire (side by side) so that I reduce the "Electrical" and Electrostatic effects of the wire on the component.

Note: The magnetically effect of the wire(s) on the component is not important for me.

Thanks.

P.S. One way is to shield the component by putting a grounded conductor between it and the side wire. But I am going to do it by using a second wire if possible....


Hy epilot,

The two fields are electrostatic and electromagnetic. Electrostatic is like capacative coupling and electromagnetic is like inductive coupling. You certainly will reduce the electrostatic coupling by using parrallel wires, but they need to be connected to a virtual ground for best effect. The amount of electrostatic screening will depend on the physical aspects of the layout. This type of parallel scsreening is commonly used on ribbon cable. I'm intrigued; what is your application?
 
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