Current-mode CMOS multiple-valued logic function realization using a direct cover algorithm

In the past, several heuristic based programs have been reported to obtain an efficient sum of product (SOP) form expression for a given MVL function using the literal, min, and tsum set of operators. HAMLET, one of these programs, includes implementation of many earlier reported heuristic based algorithms. In HAMLET, the Gold heuristic chooses the best realization after applying all other heuristics implemented. A novel heuristic based program is reported for the realization of MVL functions in SOP form using the literal, cycle, complement of literal, complement of cycle, min, and tsum set of operators. It is known that the cost, in terms of the number of transistors, of realizing this set of operators (in current mode CMOS) and that of existing sets of operators is comparable. For a random sample of 4 valued, 2 variable functions the realizations have been compared for the developed program and HAMLET (Gold). The average number of PTs required by the developed program and HAMLET (Gold) were 5.53 and 6.62, respectively.