Abstract
This paper proposes Fuzzy Programmable Logic Arrays(PLA's)that can realize fuzzy logic functions on the basic research of fuzzy computer. The fuzzy logic functions can be represented by fuzzy logic formulas composed of fuzzy AND(・), OR(∨), NOT(〜)and variables.Considering to apply the fuzzy logic functions on the engineering use, some meaningful special classes of the fuzzy logic functions have been studied, e.g., P-type and C-type fuzzy logic functions. Therefore, this paper investigates the design of fuzzy PLA's realizing the above fuzzy logic functions. First, it proposes an AND-OR fuzzy PLA as an extension of a binary AND-OR PLA and shows that the column number requires 3^n+n-1. The analysis of the maximum number of the column in a PLA is interesting for the reason why if a PLA is used to implement a function, the cost is directly related to the column number. Therefore, in order to minimize the size of PLA's, a fuzzy PLA that is constructed by an AND-OR PLA, an OR-AND PLA and an output decoder is proposed. Although the PLA requires an output decoder, the column number is saved, that is, it requires 2^<n+1>. Thus, the column number is smaller than that of the former, and the efficiency of the latter increases as the variable number of the fuzzy logic function becomes larger.
