A mixed-signal current-mode fuzzy logic controller

One of the more active areas of fuzzy logic applications is control system. The proposed controller chip results in a novel Membership Function Circuit (MFC) as well as its programmable version, a new structure for Min/Max operators, which are compatible to the proposed MFC, and a novel divider circuit for defuzzifier interface. Programmable functionalities are added by using digital techniques. This controller is a general-purpose fuzzy controller (3×3) that can be implemented in 0.04mm2 in 0.35μm CMOS technology. The maximum delay in output is about 63 ns that corresponds to 15.87 MFLIPS (fuzzy logic inference per second).