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Ground/Power plane and Crystals

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difflvl

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ground plane under crystal

Hi,

I've tried searching but haven't come up with anything.

Is it bad to have a ground/power plane under a crystal? Is it better to have a cutout under the crystal in the planes? I saw a freescale app note that suggested to do that.

Also is it bad to have a copper pour over the crystal circuit?

Thanks
 

turbina

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if in ground plane under crystal there isn't toomuch noise or current (impulsive) there is'nt no problems.
 

cyberrat

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It's better to have as much ground around the crystal as you can, keep other signals away from it.
 

    difflvl

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difflvl

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How about right under it and in between the tracks, just all over?
 

crenyen

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Crystal oscillator signal will generate multiple harmonic carriers including single tone you actually want. It better have complete ground/power on and under oscillator traces to prevent those harmonics produce EMI problems.
 

rogerynt

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Gnd plate under x'tal also helps to improve ESD performance

Rogerynt
 

s.venkatesh

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Hi
The power plane under the crystal is need to avoid for the better performance ,but the ground plane under the crystal is not make much of problems.
 

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