Orthogonal partitioning and gated clock architecture for low power realization of FSMs

Abstract

In this paper we address the issue of low power realization of FSMs using decomposition and gated clock architecture. We decompose the N state machine into two interacting machines with N1, N2 states such that N=N1×N2. Our cost function is the number of self-edges, which is to be maximized. For all the self-edge conditions, the inputs and clock of the respective machine is disabled to reduce the switching activity and therefore, the reduction in power can be achieved. We describe the greedy algorithm which maximizes the cost function. We attempt to keep the area the same by keeping to a minimum the number of flip-flops. We compared the results of our algorithm with JEDI. In one case, we could achieve a power reduction up to 67% with less area as well. Based on the results, we conclude that our approach is suitable for machines with a large number of states and less number of outputs.