[Magic-dev] Importing GDS from Astro into Magic?

[John Nestor]

Hey Magic-Dev Folks,

Has anyone tried importing a stream file generated by Synopsys Astro
Place&Route into Magic?  I'm using the Oklahoma State University flow to
generate a layout and am trying to read it back into Magic, and I'm
encountering some issues:

Hope you are doing well.  I've been trying out the Astro flow for the 0.5um
standard cells.  It seems to work OK creating the tutorial example, but I'm
having some issues reading the resulting GDS file back into Magic.  Is there
a preprocessing step that I'm not aware of?

1. The gridsize is changed when I read the stream file back into Magic to be
2 lambda.  Is this due to the fact that Astro puts things on half lambdas?
Maybe this is a feature rather than an issue.

2. The top level cell is empty.  I can find the necessary logic
in a subcell called "toppo".

3. Looking at the "toppo" subcell, there are DRC errors because adjacent
cells are placed 1 lambda apart and the well spacing rule is violated.

4. The "via" subcells $$M2_M1, $$M3_M2, $$M2_M1_1500_1500_3_1 and
$$M2_M1_1500_1500_3_3 are not getting instantiated properly in the "toppo"
cell and connectivity between layers is lost at these points.  Does magic
have issues with cell names that start with "$$"?

If anyone else has encoutered these issues or has suggestions how to deal
with them, I'd appreciate hearing from you.  I'm using Magic 7.4 rev 34.

Thanks,

John




-- 
John Nestor, Associate Professor
ECE Department
Lafayette College
Easton, PA 18042
nestorj at lafayette.edu
http://foghorn.cadlab.lafayette.edu/~nestorj