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Matthew Guthaus

11/12/2021, 5:46 PM
I've gotten some really odd power stripes in my design. These cause spacing errors, obviously. Any idea why this is?? I'm using the same pdn setup I had in MPW2.
It looks like this is vssd1 and vccd1 and perhaps that area on the side of the macro isn't wide enough to have a proper stripe so extras are inserted in...
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Matt Venn

11/12/2021, 6:31 PM
never seen anything like it
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Matthew Guthaus

11/12/2021, 7:05 PM
I'm re-running with some additional space on that side to see if it fixes things.
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Maximo Balestrini

11/12/2021, 7:57 PM
I've seen that when there is no space on the sides of the macro for both vssd1 and vccd1
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Matthew Guthaus

11/12/2021, 8:01 PM
So it seems like macros should be placed with at least 100 microns of row space on all sides. The straps have a pitch of about 100 so you need to at least guarantee that vssd1/vccd1 get connected in that space.
My example had 88.9 microns.
That is with the default strap setup.
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Maximo Balestrini

11/12/2021, 8:10 PM
yes, I had to set a smaller
FP_PDN_VPITCH
in my tests because I didn't have space to move the macro
👍 1
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Tayyeb Mahmood

11/12/2021, 8:15 PM
I have also broken PDN, couldn't find time to solve it.
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Matthew Guthaus

11/12/2021, 8:49 PM
@User what is the problem with yours?
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Tayyeb Mahmood

11/13/2021, 3:47 AM
It fails while flaging two conficting grids for several macros.