Hybrid Fuzzy Direct Cover Algorithm for Synthesis of Multiple-Valued Logic Functions

Direct Cover (DC) based techniques for synthesis of multiple-valued logic (MVL) functions have been reported in the literature. In this paper, we propose Fuzzy-based DC algorithm for synthesis of MVL functions. The proposed algorithm uses the principles of Fuzzy Logic in selecting the set of minterms and the appropriate set of implicants needed to synthesize a given MVL function. The proposed Fuzzified-Direct-Cover (FZDC) heuristic is tested in comparison with five other DC-based algorithms reported in the literature. The benchmark used in our comparison consists of 50000 2-variable 4-valued randomly generated functions. The basis for comparison is the chip area consumed in terms of the average number of implicants needed to synthesize a given MVL function. It is shown that on average the FZDC heuristic requires less number of implicants to synthesize a given MVL function as compared to those required by any of the other five DCbased heuristics.