2 Replies Latest reply on Oct 2, 2017 9:41 AM by jagladden

    Problem selecting via type

    jagladden
    jagladden Sep 27, 2017 5:05 PM

      Although I have been an occasional PADS layout user for many years, all my previous projects used netlist flow. My current project is my first attempt to use DxDesigner with the integrated flow to PADS layout.

       

      I have two via types defined, MEDIUMVIA (40 mil pad, 25 mil hole) and TINYVIA (25 mil pad, 15 mil hole) in addition to STANDARDVIA. Both are "through" vias. However, after I select one of these two vias for placement (RMB->via type) when I place a via while manually routing the resulting via is always of type STANDARDVIA. Furthermore, if I select a previously placed via and then try to change its type via the properties window to either TINYVIA or MEDIUMVIA, the attempt fails and I see "Violation detected" on the message bar at the bottom of the window.

       

      I'm guessing there is some sort of constraint issue, but I can't find a seemingly relevant constraint.  I would appreciate suggestions as to how I might resolve this problem, as I am currently stuck.

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        • 1. Re: Problem selecting via type
          vinayarora
          vinayarora Oct 2, 2017 5:58 AM (in response to jagladden)

          Make sure Vias are available

          Setup\Design Rules\Default\Routing

          • 2. Re: Problem selecting via type
            jagladden
            jagladden Oct 2, 2017 9:41 AM (in response to jagladden)

            After receiving help form Mentor tech support, I can now answer my own question.  When using integrated flow, the following rule apply regarding via placement:

            1) RMB->Via Type is a NOOP - it's still there but it has no effect on the type of via that will be placed.

            2) The property window cannot be used to change the type of an existing via to any type other than that specified as the default via for the net class.  Anything is else is a violation.

            3) A net class can have only one default via type

            4) To place a via of a type other than the net class default, you must first use Setup->Via Spans to change the default via - even if all the via types are "through"

             

            Not exactly convenient, but it works.