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how low frequenct signal affects the high frequency signal

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MK28

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Cross talk!

What is cross talk? Is it an issue, if the IC has some inductors ? Could anyone please explain it or give me a site where i can find some info.
 

ceaser

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Re: Cross talk!

simply cross talk happen if two wires carrings the signal is adjacent; so they affect each other in high freq operations
it is not an issue because it cause undesirable interference bettween signals
i think you should look in this site; it can explain it better than me
www.howstuffworks.com
 

alenhan

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Cross talk!

I think cross talk sometimes is an issue, it can be decreased by special layout routeing,
 

sivani_vs

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Re: Cross talk!

Cross talk occurs if the signal gets coupled to the nereby ckt. the key concept is mutual inductance. its ok using inductors, but see that it is not mutually coupled to near by inductor.
 

yeewong_su

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Cross talk!

Can easy think that the effect happen when cross some thing on it
 

lavitaebelle

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Cross talk!

Crosstalk need not happen only due to mutual coupling. Along with the AC effect, there is a DC crosstalk component also. This is due to sharing common ground and supplies between various blocks. Sharing common ground means that any change in the current in one block results in ground level change and hence affecting another block.

Mainly layout techniques like reducing coupling by placing current carrying wires far away, inductors far away and having different grounds for different blocks, connecting grounds and supplies only at the pads are used to reduce crosstalk
 

sambireddy

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Cross talk!

crsoo talk will definitely occur when two wires carrying different high intensity signals travel together or cross each other, due to the mutual inductance of each wire. to avoid this all such lines should be shielded with ground or probably any stable signal. in case of inductors this is very important that the field produced in it should not disturb any other near by signals .so, proper shielding should be provided for the inductor.
 

vlsiattitude

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Re: Cross talk!

cross talk is an issue if one of adjoining signals is of high frequency and one them is sensitive.

u can avoid it by running groung line between the two signals
 

omsi

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Cross talk!

in ic layout design, when the two conducting layers run parallelly, there is a sidewall capacitance that comes in to picture.the signal from one layer will be coupled to another due to capacitance.this is cross talk.
there r 2 ways to eliminate this.
1. increasing the spacing of layers.normally 20% extra than minimum spacing.
2.by sheilding the layer with extra metal connected to ground .
 

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