4 Replies Latest reply on Feb 2, 2012 5:34 AM by volker.hetzer

    Which part properties are used by the packager?



      In our current design flow we have set "Part Name", "Part Number" and "Part Label" on all our components.

      Only, we don't know which ones are really necessary. As a precaution we set Part Name and Part Number to the same values. And we mostly ignore Part Label.


      So, which property MUST be on the part in the schematic in order for the packager to work? When I delete all three properties, the packager complains. Is there a search order in the packager?

      Generally, how does the packager find the cell and pin mapping, given a schematic symbol?


      Lots of Greetings!

        • 1. Re: Which part properties are used by the packager?


          The answer is that all three are used if they exist. As a minimum Part Number is all that is required, but of course you can use one symbol with the same Part Name for many parts, in which case there is a 'default' radio button in the Part Editor. For example say you have a symbol Res with a Part Name = Res. If there are multiple parts in the library that use this symbol then you will have multiple Part Name = Res in the library, one for each Part Number, say R0603, R0805 etc. Then you can decide which will be selected if you don't put a Part Number on the part. If on the other hand you use unique Part Name/Part Number combinations then either property will work. Also note that if you use all three properties then packager will check against all three and if one mismatches will fail. Part Label, like Part Name does not have to be unique, Part Number must be.

          Does this help?


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          • 2. Re: Which part properties are used by the packager?

            "Does this help?"

            Almost. :-)


            Here's what I understood:


            The Part Number is required to be unique. Nothing else is.


            1. When the Part Number exists on a symbol in the schematic:
              • the packager goes to the lmc file (does it?)
              • uses the Part Number as key in order to extract the pin mapping and miscellaneus properties, like "Cell Name" or "Our Nice Property"
              • sets the properties on the schematic symbol and its pins, taking into account sectioning and presumably doing some sanity checking as well, like whether the symbol in the schematic is even allowed for that part
            2. When no Part Number, but a non-unique Part Name exists, the packager finds all matching parts and picks the one that has the "Default" flag set.
            3. If the Part Name is unique too, scenario 2 behaves like scenario 1.


            Is this ok so far?


            But what's the intended role for Part Label?


            Lots of Greetings!

            • 3. Re: Which part properties are used by the packager?

              Part Label is just an extra field you can use for any other purpose. In the companies I worked at we used it for a generic specification such as CECC or vendor specific part number. You may choose to use it or not, but if it is used it will also be checked against the part in the schematic.


              1. Unique Part Number no Part Name - packager looks up corresponding part in the LMC

              2. Unique Part Name no Part Number - packager looks up Part Name and uses corresponding Part Number.

              3. Non-unique Part Name - packager uses the Part Name corresponding to the Default to look up Part Number.


              Other combinations it checks Part Name vs Part Number vs Part Label, though I'm not sure in which order (I'd guess at the order I've listed here).

              • 4. Re: Which part properties are used by the packager?

                That clears it up nicely.


                Thanks a lot!