2 Replies Latest reply on Mar 7, 2017 10:36 AM by cgoldenbus

    internal unused pads and design rules

    cgoldenbus

      Mornin All,

      Okay so I am a PADS user and an relatively new Expedition user and I have an issue with how expedition handles positive planes.

      In PADS I can define my planes so that I remove unused pads on internals and then set a design rule from drill to copper, this way I reduce the clearance openings in my internal planes and help avoid huge voids.

       

      What I find in Expedition is that the Plane processor happens at the end at gerber so there is no way to create a design rule against that particular parameter so I have to try and push and shove vias around to eliminate plane breakouts and cuts due to via clearances.

      Seems after all this time and with the increased densities It'd be smart to add a design rule set as such to open up channels on internal layers.

       

      Now I find we can define via spans so now does that have to be a completely different via for each layer I want connected? e.g.

      Assume no blind vias all through :

      via from top to layer 3   - pad = top- layer 3 and bottom?

      top to layer 6    - pad = top - layer6  and bottom?

      If I try to define the via as such its invalid because  I already have an 8 layer via span or I'll get an invalid range

       

      Or can a via be classified as skip via and then will it only connect to required layers plus top and bottom?

      I tried this and my planes got disconnected

       

      Any insight, thoughts, or comments into the via thing?

       

      Thanks All.

      CG