Fix the negative Setup time question

[stn0795]

I see few questions and answers for the negative setup time from this forum. I have a question similiar that how can and how many ways we fix the negative setup time? Which fix the negative Setup time will impact the Holdtime?
Thanks,
stn

 

[songzm2008]

Fix setup violation you can insert buffer,optimize fanout,upsize instance
If you fix the setup you must large the require time,so it must inpact the holdtime!

 

[srideepa]

Hi,
Fixing setup violation of a path to a margin (Say just getting a +ve slack) cannot result in hold violation. But the same endpoint may have many paths with different start points which can have hold violation as the result. Hence fixing setup violations should target cells that are having minimum fanout so that the impact is also minimum.

On the other hand a whatif analysis in PrimeTIme is worthy for such paths.

On your question, a negative setup time is just a requirement similar to positive one. You will use the same strategy as fixing +ve library setup time to fix this.

Regards,
R.Srideepa