A New Highly Controllable and Accurate Algorithm for Defuzzifier Circuit Implementation


1 Department of Electrical Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.

2 Department of Electrical Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran.


Defuzzifier circuit is one of the most important parts of fuzzy logic controllers that determine the output accuracy. The Center Of Gravity method (COG) is one of the most accurate methods that so far been presented for defuzzification. In this paper, a simple algorithm is presented to generate triangular output membership functions in the Mamdani method using the multiplier/divider circuit and mirror current CMOS technology. As well as the method simplicity, the method is highly accuracy and controllable in the height, slope of output membership functions, number of rules and number of input/output membership functions cause to use mixed voltages. This method covers each type of the input fuzzifier. The proposed Circuits in this paper are implemented by a standard 0.35um CMOS technology in Hspice software


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