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 Changing layer numbers in a design library 

Last post Wed, Jun 19 2013 1:31 AM by Lynks. 2 replies.
Started by Lynks 14 May 2013 02:03 PM. Topic has 2 replies and 738 views
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  • Tue, May 14 2013 2:03 PM

    • Lynks
    • Top 500 Contributor
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    Changing layer numbers in a design library Reply

    We created a library using a custom technology file where different layers were assigned arbitrary layer numbers in IC6.1.5-64b.500.8. Now we want to take that same library and use it with a much larger technology file which will add additional layers and include all layers previously defined in the custom technology file we had. Unfortunately, there are some conflicts in the layer numbers.

    At this point, we've edited the larger technology file so that all the layers from the custom technology file have been assigned to available layer numbers. Now because the layer numbers are different, the polygons in the design library do not show (only the polygons whose layers just so happened to have the same layer number as it originally had actually showed correctly).

    One idea we've tried is to stream out the design library to a GDS file and create a layer mapping. I would take take the layer name that was obtained from the custom tech file and map it to a stream layer number. The stream layer number I'd choose would be the same number as this layer would appear in the larger tech file. Then I would stream-in the GDS file back into Virtuoso with the larger tech file attached. Even in this manner, I got a similar result as mentioned previously. As a test, I streamed in the GDS file again with the custom tech file attached instead and everything looked good. It seems like the layer mapping didn't affect the layer numbers. Perhaps, I missed an important step here.

    In the end, I simply want this design library which was originally made using a custom tech library, to work with this larger manually merged tech file where the same layers from the custom tech library are now using different layer numbers. Does anyone know of a simple way to do this?

    Any help is appreciated. 

    • Post Points: 20
  • Thu, Jun 13 2013 6:09 AM

    • Quek
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    Re: Changing layer numbers in a design library Reply

     Hi Lynks

    Your idea of exporting/importing gds is good and should work:

    a. With the design library still attach to the original custom techfile, export the design in gds format

    b. Map the gds numbers to the appropriate layer names in the newly merged large techfile

    c. Import the gds files

    I don't think that there is really any other good, less troublesome method of resolving this situation.

    Best regards
    Quek

    • Post Points: 20
  • Wed, Jun 19 2013 1:31 AM

    • Lynks
    • Top 500 Contributor
    • Joined on Tue, May 14 2013
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    Re: Changing layer numbers in a design library Reply

    Thank you for the follow up, Quek.

    Yes, actually we managed to get it to work through this method. In our first attempt, the newly merged techfile was created such that we assigned layer names to layer numbers that were first available in the large list (e.g. say layer numbers 1, 3, 4, 5, 7 are taken so we started with 2, 6 and so on). In our second attempt, we simply moved the layers to the very end of the list so that they're all together (e.g. last defined layer is 100, so we started integrating the new layers from 101 and on). I guess this helped to minimize any mistakes in the layer mapping as the new layers are adjacent to each other numerically. The procedure with exporting the gds, mapping the gds numbers, and importing the gds remained essentially the same.

    So yep, it does in fact work. 

    • Post Points: 5
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Started by Lynks at 14 May 2013 02:03 PM. Topic has 2 replies.