A 12 b resolution 200 kFLIPS fuzzy inference processor

A fuzzy inference processor that performs fuzzy inference with 12-b resolution input at 200 kFLIPS (fuzzy logical inferences per second) is described. Three techniques are adopted to attain this performance: (1) membership-function generators constructed of combinational logic, which calculate a membership-function value in less than half of a clock cycle; (2) rule instructions that execute one-rule-by-one instruction in an antecedent unit; and (3) an improved add/divide algorithm that calculates a centroid in a consequent unit. The block diagram of this processor is shown. The chip, fabricated by 1- mu m single-polycide, double-metal CMOS technology, contains 86-k transistors in a 7.5-mm*6.7-mm die, and is packaged in an 80-pin flat package. The chip operates at more than 20-MHz clock frequency at 5 V.<>