8 Replies Latest reply on May 20, 2013 11:52 AM by jduquette

    problem with parts not loading in from library when importing net-list?????

    shkang

      Software: PADs layout and Logic Version 9.4

       

      I am trying to import a net-list derived from logic into pads layout but I get import errors saying it cant find some parts even though they are in the library.

       

      example:

       

      No decals assigned for part type CON\HDR\24L

      Can't find part decal item < PCBNULL >

      J12     CON\HDR\24L@CON\PANASONIC\AXK724147G\24L

       

      CON\HDR\24L is a generic part for a 24 pin header and has no decal assigned in the library.

       

      The decal (PANASONIC\AXK724147G\24L) has been assigned in the schematic using the PART PROPERTIES box which assigns/associates the decal which gets included when you generate the netlist.

       

      So is this a limitation of Pads, a bug or is am doing something wrong? I'm unable to find anything useful in the help files apart from the ASCII help which states the when you import an ASCII it looks first for the PART name then DECAL name from the library lists (which are all shared and allow searches).

       

      Normally the decal is assigned to the part in the library and isnt a problem but why have a function to assign a decal in the schematic in the first place if it doesn't work?

       

      BTW I tried modifying the netlist to see if PADS could find a part if I manually changed a part with a library assigned decals  to another decal

      eg changed CAP\0402@C0402  to CAP\0402@C1210.

       

      C1210 is not associated to the PART type but PADS was able to find it in the library and import into the design......so why can this be found and not the other parts? They are all stored in the same library?

       

      Has anyone else experienced similar problems or can point out where I am going wrong?........its been a long day!!!

       

      Martin


        • 1. Re: problem with parts not loading in from library when importing net-list?????
          Mentor_JanetD

          Every PCB Decal must have a corresponding Part Type that calls out that decal on the PCB Decals tab. Decals not called out in a Part Type will not come into the board correctly.

           

          Please see this Tech Note for more information:

           

          https://supportnet.mentor.com/reference/technotes/public/technote.cfm?tn=mg28076

          • 2. Re: problem with parts not loading in from library when importing net-list?????
            shkang

            OK thanks. I understand how to assign a decal to a part in the library.

             

            I dont think I worded my question very well but I was basically asking when you assign a decal at schematic level why pads layout couldnt find the parts/decals the netlist was asking for?

             

            I have since got round the problem but assigning a dummy decal with same number of pins as defined by the parts data and saved in parts library.

             

            Then when you assign a decal to the part in the schematic design - pads layout can now find the parts/decals the netlist is asking for.

             

            So basically you cant assign a decal in the schematic if the part has no associated decal in the libray - unless you assign a dummy placeholder decal to it first.

             

            M

            • 3. Re: problem with parts not loading in from library when importing net-list?????
              monkey15007

              I met the same problem, i found that assign a decal by part properties does not work. i want to know if you have solve the problem. could you do me a favor? thx.

              • 4. Re: problem with parts not loading in from library when importing net-list?????
                jduquette

                I'm assuming you are talking about getting a part from Logic to Layout.

                 

                The part needs to be in a library.  If you edit the part in Logic, you then need to save the part back to the library before you ECO to Layout.  Be careful that if you changed any attributes on the part, you are going to update the attributes in the library when you do this.  IMO, it is much safer to edit the library directly and then update Logic.

                 

                Check your library sort order.  If you have a part defined in mutliple libraries (it is easy to accidently do this when saving) then PADS is going to use the one from the library closest to the top of the list (the first one it finds).  If you changed another copy, the ECO process will never see the changes.

                • 5. Re: problem with parts not loading in from library when importing net-list?????
                  monkey15007

                  My English is limited, so maybe i didn't express myself very clearly. The part is in a library and it has many PCB decals. For example, RES is a part in a library and it has  multiple PCB decals, such as 0805, 0603, 0402, i assigned 0603 as RES's PCB decal, using part properties in Logic. When i ECO to Layout, PCB decal change to 0805 (0805 has a high priority level). I don't know why.

                   

                  There is another problem. there is a part, such as RES. It in in a library and has two PCB decals (0805 and 0603).  There are two RES in schematic diagram and i want one's PCB decal is 0805, another is 0603, how can i achieve it ?

                   

                  I am not sure that you are cottoning onto my sentence.

                   

                  thank you for your answer.

                  • 6. Re: problem with parts not loading in from library when importing net-list?????
                    jduquette

                    PADS isn't very friendly about this much variation on a part.  Instead of one res component I keep a generic library with a R0402 and a R0603 and a R0805, etc.  I minimize the multiple decals; I might use them to have multiple anode marking options for diodes.  In my mind the schematic designer needs to know the size of the part they want placed on the PCB; power dissipation is the main reason.

                     

                    In Logic:

                     

                    Select R1

                    <right-click>(Properties) and then press the 'PCB Decals' button - Assign 0603

                     

                    Select R2

                    <right-click>(Properties) and then press the 'PCB Decals' button - Assign 0805

                     

                    This might ECO to Layout without further interaction.  If not:

                     

                    In Layout:

                     

                    Select R1

                    <right-click>(Properties) and set the decal to 0603

                     

                    Select R2

                    <right-click>(Properties) and set the decal to 0805

                     

                    PADS will keep the decal info in the design files.  When you 'update from library' you may need to repeat these steps.

                    • 7. Re: problem with parts not loading in from library when importing net-list?????
                      RLS2004

                      Note that there are some potential problems related to multiple choice Part types (EG part type "RES" with several optional footprints "0805, 0603 and 0402").

                       

                      1) Assume you are currently working on a project with RES included and lots of 0805 and 0603 parts. If the engineer wants to add to the part type RES another footprint 1206, you could be in trouble. When you add 1206 to the part type in the library everything is good, but when you bring the updated part type into the current Pads Layout problems begin. ECO changes EVERY instance of RES (no matter what footprint is currently in the design) to the FIRST footprint in the list of available footprints. At the same time it will likely rotate the part, screwing up the routing unless you have been VERY careful to create ALL the available RES footprints with the SAME Zero orientation.

                       

                      2) It may be difficult to pass the layout to 3D mechanical cad like Solidworks or ProEngineer. Check to see if the part type or the footprint is used by 3D cad. The multiple footprint are a problem if only part type is passed.

                       

                      Recommendation:  Have  1:1 relation between part type and footprint.