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  3. How to prevent flooding under components?

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How to prevent flooding under components?

Manfred1
Manfred1 over 3 years ago

Hi!

I have relatively large SMD ceramic capacitors. Their symbol does not contain a keepout area, which is O.K. I want to prevent the system from filling the whole area underneath the capacitors (except the positive pin + surrounding) with GND plane. I simply have to draw a rectangular shape under the capacitor. How is that shape called? Void, cavity? What is the correct layer: Etch, Anti Etch, something else?

Kind regards, Manfred

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  • RFinley
    0 RFinley over 3 years ago

    Open the footprint, add a polygon to the Route Keepout> class, then you have a choice of Top> Bottom> All>

    Works for copper floods and flags a DRC for CLines that coincide.

    Update footprints in your design.

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  • Manfred1
    0 Manfred1 over 3 years ago in reply to RFinley

    I use the same capacitor symbol at an other place in the same layout, where I am forced to route under it. That prevents me from changing the symbol.

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  • avant
    0 avant over 3 years ago in reply to Manfred1

    Simply delete the route keepout shape on the board layout for that particular instance.

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  • avant
    0 avant over 3 years ago in reply to Manfred1

    Simply delete the route keepout shape on the board layout for that particular instance.

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