Programmable fuzzy logic device for sequential fuzzy logic synthesis

A programmable fuzzy logic device (PFLD) is proposed for sequential fuzzy hardware design. Fuzzy automata are classified into ten categories according to properties of inputs, states, and time intervals. Among the categories, a most general one called generalized fuzzy automata (GFA) is defined and its powerfulness is proven. From the GFA, we derive the structure of PFLD and develop a new sequential fuzzy hardware design methodology. The PFLD capability for synthesizing each of the categories is shown to ease design process. A PFLD includes generic LR fuzzy cells, current memories, and common analog current mode devices. The novel switch-current scheme makes target sequential fuzzy logic circuits possess high performance, low power, and compactness advantages. Two well-known fuzzy state machines, a fuzzy temporal knowledge system and a fuzzy feedback controller, as examples are realized with PFLDs