Embedded low power analog CMOS Fuzzy Logic Controller chip for industrial applications

The paper presents an analog low power CMOS fuzzy logic controller (FLC) chip implementation and its application to an industrial chemical reactor. This approach employs a simple architecture that contains three stages namely Fuzzification, Inference Engine and Defuzzification. The Fuzzifier circuit generates high precision membership functions (MFs) that are easily tunable by changing the voltages in IC pins. The FLC chip has three input MFs and five output MFs. The two input minimum circuits were used to design the Min-Product inferencing for inference engine. Defuzzification circuit is well designed to reduce the size of the chip. The proposed chip has power consumption of about 10mW. The whole chip area is less than 0.5mm². The resulted chip shows simple structure, good performance in processing speed, also enough flexible to compete digital fuzzy approaches, area consumption and accomplished with less reconfigurable rules, a speed of up to about 8 MFLIPS (Fuzzy Logic Inference Per Second) has been achieved. The results show a good functionality of controller in response to confirm the success of the design. The application of the system to an industrial chemical reactor in a feedback loop is considered.