How do you manage routing with strict clearance rules?

[ale210]

Hi, I'm trying to explain fine, because english is not my native languaje.

I'm routing differentials tracks, I setted some diff rules, like width and clearance, then my track it has a 0,18 mm width and 0,25 mm of separation between it. Next, for add clearance between other elements such cooper, other diff tracks, I configured a clearance rule establishing 0.50 mm (0.25 * 2 as recommend for differents lanes of diff tracks), the problem is when i routing near the pads of the IC, i can't routing because i'm violating rules!!! So, in this case either disable the rule or use ignore obstacles (shift + R).

Someone knows any other method? How do you routing, in this cases?

Best regards!

[robertferanec]

Usually I use a stackup where I am able to route between pads. If you can not use custom stackup or if you have a very high density chip, often people create an area (room) with special clearance rule.

- Stackup examples: https://welldoneblog.fedevel.com/201...your-projects/
- Rules with special rules: https://welldoneblog.fedevel.com/201...-or-footprint/