Fixing up setup violation on critical path

[limitless_21]

Hi All,

Though there are many ways to fix setup violation coming in your design.
2 of the most methods used up are - Upsizing of the cell ( critical path ) and adding the buffer.
Wanted to know what is the criteria for using up any one of the method for a particular critical path.

Regards
Limitless

 

[navin_2cool]

To fix the setup violation, one need to reduce the data path delay. So as you only suggested that it could be done through either up-sizing the cell or adding the buffer. Adding the buffer will need extra space as well as routing resources where as up-sizing the buffer will have advantage in terms of area. Adding the buffer will ONLY help if the transition on the path is bad and you want to improve it by adding buffer otherwise it will only add to the data path delay. And if the transitions are bad, i will suggest to add a pair of inverters instead of buffers to reduce the data path delay.