Analysis of minimization algorithms for multiple-valued programmable logic arrays

The authors compare the performance of three heuristic algorithms for the minimization of sum-of-products expressions realized by the H.G. Kerkhoff and J.T. Butler´s (1986) multiple-valued programmable logic arrays. Heuristic methods are important because exact minimization is extremely time-consuming. The authors compare the heuristics to the exact solution, showing that heuristic methods are reasonably close to minimal. They use as a basis of comparison the average number of product terms over a set of randomly generated functions. All three heuristics produce nearly the same average number of product terms. Although the averages are close, there is surprisingly little overlap among the set of functions for which the best realization is achieved. Thus, there is a benefit to applying different heuristics and then choosing the best realization.<>