K-maps: a vehicle to an optimal solution in combinational logic design problems using digital multiplexers

Abstract

Application of Karnaugh maps (K-Maps) for the design of combinational logic circuits and sequential logic circuits is a subject that has been widely discussed. However, the use of K-Maps in the design of combinational logic circuits using medium scale integration (MSI) devices has not yet been widely explored. The techniques discussed in this paper, were devised, and implemented by the author as an attempt to resolve the problem of not having a criterion to determine an optimal design solution, when students presented several different designs. The devised method entails the designer to solve three distinct problems. First is an assignment problem, i.e. assigning input variables to select lines of the multiplexer. Each assignment results in a different assignment K-Map. Secondly, is a simplification problem i.e. finding the most simplified solution of each of the assignment maps. Lastly, is an optimization problem. Key Words: Karnaugh maps (K-Maps), combinational logic circuits, optimal design solution, multiplexer, simplified solution Botswana Journal of Technology Vol.13(2) 2004: 29-34