I’m trying to route some sensitive high frequency lines which should maintain 0.5mm clearance into a footprint which has a tighter pitch. This causes many many many DRC violations. I would like to reduce the clearance requirement to 0.1mm when the track is inside a footprint courtyard to avoid this issue. I set up the rule:
This, however, causes the entire length of the track to get 0.1mm clearance, not just the part inside the courtyard (even sections of the connected track which never touch a courtyard). How do I do this correctly?
I have never tried what I write here and I have never used rules.
If using what paulvdh suggest will not work for you I suppose it is possible to:
make a Rule area (giving it a name),
make a rule reducing clearance inside this area.
If it also not works the last (and I’m sure it will work) is to use net-ties at all tracks going to that IC and having different clearance for nets on both sides of net-tie.
Unfortunately the rule system doesn’t work that way. All rule tests while routing or while running DRC are made for items, not areas. An area in a rule condition is used to choose the items to which the rule applies. A rule either applies to a certain item or it doesn’t. Rules aren’t actually applied to areas. Different rules can’t be applied to different parts of items.
The difference between “inside” and “intersects” is in how an item is chosen for the rule: either the item is totally inside the area, or it needs to only intersect that area.
If you need to change the rule in an edge of an area, you have to cut the items. It’s not difficult with tracks, but editing may become more difficult because you have to keep the seam between the segments in the correct location.
