Pruning Strategy
Need to keep more than just worst case delay (Drmax and Dfmax) or we may fall into a local minima
Keep Delay is: Dr > Drmax x P or Df > Dfmax x P where P is a user defined pruning factor (0.6 - 0.9)
- If 0.9, keep all delays which are within 10% of max delay.
Do the same for Slew Rate
- Sr > S(Drmax)
- Sf > S(Dfmax)