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What is the effect of traces like this?

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alireza

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Hi guys,
In many PCBs i have seen a small part of a trace is routed snake-like (as shown in attached picture).
I am wondering what it is for? what is its effect? for which type of signals
it is needed to be routed like this?

I would be grateful if a professional clarify this matter for me.

Alireza :roll:
 

FANT

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It is just a delay line made to make all the signals from a bus received at the same time, because the delay depends on the trace lenght.
On the shortest traces you need to delay in some way the signals, to make the signals appear on the bus at the same time.
Hope is enough.

Mandi
 

kschan

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This for high speed board design and on parallel data bus. The term use for this call 'trace lenght matching'. The purpose has explained by alireza.
 

arcaphill

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The serpentine line is just for timing delay!!!
 

chinara

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Another thing should be noted is the distance between the clock trace segments. The distance should be larger than 3 times trace width and the clock segments should be small.
 

amjad

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This type of traces are purposefully done to make the signals TRAVEL same length from source to destination we call these as EQUAL LENGTH TRACES.

FOR example if the board as 200 traces and if some traces have take long time to reach destination and some traces reach soon then we make these short traces match its length with long time traces by this "EQUAL LENGTH" PROCEDURE
 

tennad

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Snake trace keep trace length to satisfy system constraint
 

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