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The geometrical size of the cells bigger then size of device in my extracted view

TiNat
Hello, I have two technology libraries similar each other. At the first library the geometrical size of the cell at extracted view like the geometrical size of the extracted device (look at fig.1 and fig.2 at attached file). At the second library the geometrical size of the cell at extracted view bigger the geometrical size of the extracted device (look at fig.3 and fig.4 at attached file). I don't understand why this situation has occurred. I copied extract rules and auLvs view of element from the first library to the second. After that I had the same result. Who can help me? When geometrical size of the cell at extracted view bigger the geometrical size of the extracted device, it is not error in IC design but it is uncomfortable because cells are overlap each other. Thank you for your solution.
screen-shots.zip

  • Hi TiNat

    Just as what you have written, it does not matter that the outlines of the symbol of the cells in the extracted view overlap each other. When a netlister reads an extracted view, only the net connectivity info in the extracted view matters. Regardless of the size of the extracted view, you will be able to get a correct netlist. You can reduce the size of the cells for the 2nd tech library as follows:

    a. Create a text file "myFile" with the following contents
    myTechLib2 cell1 symbol auLvs 15
    myTechLib2 cell2 symbol auLvs 15
    ...

    The above means "magnify the symbol view by 15 times and copy it as a auLvs view".

    b. Enter the following in ciw:
    ivCreatePCells("myFile")

    Best regards
    Quek

  • Thank you very much Quek for your answer, but this method I know. It reduces the size of symbol but not the size of extracted body. In my figures you can see that the symbols have the same size but borders of the extracted body are different. It is difficult to understand why it occurred, some times ago all were ok.

  • Hi TiNat

    The shapes in the extracted view do not matter too. They are just for easy viewing. In fact, we can have an empty extracted view (without the shapes) and it will still work fine. The shapes saved using saveDerived or saveInterconnect cmds in tech2 extract rules file might have been sized up and hence they appear bigger than the same shapes created using tech1 extract rules file. Perhaps you might want to use vlw and ?keepData=namedLayers option to trace the shapes.

    Best regards
    Quek

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