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Virtuoso Layout: instance boundry

MarkusK

Hello everybody,

I sometimes see a strange behaviour when creating a layout in IC6.15:

Starting at some time (do not know when/why) doing a fit does fit the layout in the middle of the layout editor, but there is a huge black area around it. So the size of the layout (rectangle form) shown is <<50% of the available area in x and y direction. When adding this block into an other layout, Virtuoso indicates a very big device size/boundry (dashed line) when hoving over the block.

I know this might happen if a small device/path/contact is placed outside of the main layout block (and due to its small size it might be nearly unvisible).

But: I (and my colleagues) have checked for such things about 100 times (including changing the visability and selectivty of layers, changing the shown layers at the Techfile, marking & deleting everything outside the block, ...). We are absolutely sure that there is no device left outside of the instance's boundry!

Has anybody an idea what might cause this behaviour and how we can get rid of that effect?

The only way we found yet, is to copy the whole layout into a new layout cell...

 

Thank you very much!

Best regards,

Markus

  • Hi Markus,

    This may be happen when you switch between using Virtuoso-XL and Virtuoso-L.

    If you make edits in L, it is possible that objects related to connectivity are not properly cleaned up by the editor.

    This was a problem in earlier software releases.

    You may have some route objects or steiner points that are in the database and are resulting in a larger than normal cell boundary. These are not normally visible, but they have coordinate information that will mess up the display

    Try using the following  SKILL command (in XL) to clean up the connectivity:

     lceClearLogicalConn(geGetEditCellView())

     Then re-run the extractor (if you want connectivity in your layouts).

    This should remove the steiners and any other phantom route objects.

    I hope this will fix your problem. If not, re-post. I may have another idea.

     Colin

     

  • Hello Colin,

    thank you for this hint.

    We tried it, but we it didn't solve that issue :-(

    I'll update the software to the most recent version. If it will occur again, I will send an other post :-)

    Best regards,

    Markus

     

  • Hello Colin,

     we are facing the same problem.

    Unfortunable your proposal doesn't fix this.

    What about your other ideas?

    Thanks Werner

  • Hi Werner,

    It is possible that there are steiner objects that are causing this problem.

    Try this in the CIW:

    foreach(st geGetEditCellView()~>steiners dbDeleteObject(st))

     

    Hope this helps

     

    Colin

  • Hello Colin,

     thank you very much! For my design(s) this works great!

    Best regards,

    Markus

     

  • Hello Colin,

    running extract after deleting the Steiners and the Boundary is as it should be.

    Thanks for the solution.

    Regards

    Werner

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