An optimal algorithm for sizing sequential circuits for industrial library based designs

Abstract

In this paper, we propose an optimal gate sizing and clock skew optimization algorithm for globally sizing synchronous sequential circuits. The number of constraints and variables in our formulation is linear with respect to the number of circuit components and hence our algorithm can efficiently find the optimal solution for industrial scale designs. To the best of our knowledge our method is the first exact gate sizing algorithm that can handle cyclic sequential circuits. Experimental results on industrial cell libraries demonstrate that our algorithm can yield an average of 12.6% improvement in the optimal clock period by combining clock skew optimization with gate sizing. For identical clock period, our algorithm can achieve an average of 11.3% area savings over a popular commercial synthesis tool.