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Allegro: How to set the clearance between two grounding plane

AdamSmith

Hello all.

Right now I have a board. I want to add two grounding planes, one at top, one at bottom. My aim is going to set the gap to be 15 mil ( also known as clearance). I worked with KiCad for sometimes before, and it lets you to enter the clearance value when creating the copper-filled grounding plane. But how to do it in Allegro? Any suggestion? Thanks.

And by the way, I have a very simple circuit with just a few resistors. But when I try to connect them together, I got DRC error on every traces I added. It all says, 'line to line spacing. Actual value:0' or 'Max neck length. Actual value: 0'. I have no idea why they came out. I really could use some help here. Thanks again.

Smith

  • oldmouldy
    You need to start with a Schematic, or netlist of some form, to get Net names and connections assigned, then you can use the Constraint Manager to control the design Parameters, otherwise you will be in a "world of Dummy Net" which isn't considered to be a Net at all by PCB Editor.
  • AdamSmith

    Hello oldmouldy:

    Yes, I imported the netlist from my schematic. Earlier today I created a new board and re-imported the netlist, and then all DRC errors are gone. Still don't know why through.

    And, do you have any idea how to change the clearance between planes? I tried few setting in Constraint Manager but none of them seems working. Thank you.

  • oldmouldy

    Planes, in PCB Editor parlance, would be "Layers", adjusted in the cross-section. Copper on the same layer would be Shapes, adjusted by Shape to Shape in the Constraint Manager, either Spacing, for different Nets, or Same Net Spacing for the Same Net on both Shapes, a Property of Void_Same_Net would have to be assigned to get one Shape to not merge with another if they have the same Net assigned. Normally, Shapes would be Dynamic, automatically clearing conflicting objects, but could be Static in which case, conflicts with other objects DRCs would abound, typically flagged as DRCs.

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