Does anyone know how OpenLane's default `IO_PCT=0....
# openlanem
Matt Venn
03/30/2023, 1:55 PMDoes anyone know how OpenLane's default
IO_PCT=0.2d
Dario Quintero
03/30/2023, 2:20 PMMaybe this sheds some light? Matt Liberty posted this STA document a few days ago. Page 203 https://vlsitesting.files.wordpress.com/2017/02/ref-for-unit6.pdf
v
Vijayan Krishnan
03/30/2023, 2:45 PMYes 20% applied by default.
m
Matt Liberty
03/31/2023, 2:17 PMIf you use too small a value then you get lots of hold buffering around the inputs. 0.2 is just a heuristic value to avoid that. If you have a more realistic set of constraints you should prefer them
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Matt Venn
03/31/2023, 4:29 PMthanks
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Tobias Strauch
04/01/2023, 5:25 AM@Matt Liberty Sure about that (the hold buffering) ? It's a max constraint, not a min.
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