ABSTRACT

Abstract?Two errors have been found in the classical theory of two-level minimization of multiple-output switching networks. First, the prime implicant theorem must be modified to cover certain degenerate cases, and second, the widely accepted notion that there can always be found a miinimal network corresponding to a set of equations that are entirely sum-of-products or entirely product-of-sums is incorrect in a less trivial way, viz., sometimes the minimal network corresponds to a mixed representation (a set of equations some of which are products-of-sums and the remainder of which are sums-of-products). Counter examples are displayed to support these claims. Networks are exhibited in which AND gates feed AND gates.

INDEX TERMS

Index Terms-Bipolar, free inversion, minimization, multiple output, prime implicant.

CITATION

P. Weiner, T.F. Dwyer, "Discussion of Some Flaws in the Classical Theory of Two-Level Minimization of Multiple-Output Switching Networks",

*IEEE Transactions on Computers*, vol. 17, no. , pp. 184-186, February 1968, doi:10.1109/TC.1968.227409CITATIONS