The timing models used in current Static Timing Analysis tools use gate delays only for single input switching events. It is well known that the temporal proximity of signals arriving at different inputs causes significant variation in the gate delay. This variation in delay affects the accuracy of our timing estimates. In this paper, we derive simple analytical models for incorporating the effect of simultaneous multiple input switching events on gate delay. The model presented requires minimum additional characterization effort, and can be employed in a statistical timing engine. The dynamic delay variability of a path caused by MIS noise can be accurately estimated using the proposed model.
Rajeshwary Tayade, Sani R. Nassif, Jacob A. Abraha