Abstract: A fuzzy inference coprocessor VLSI chip, F200, was designed as a fuzzy logic controller and fabricated with 0.8 μm CMOS technology. The chip is mainly used for the real-time process control and other suitable applications, such as robot control, classification, expert systems, and so forth. F200 can work with multiple fuzzy knowledge bases and support two types of most useful fuzzy models, Mamdani and Takagi-Sugeno model. The chip has the precision of 12 bits. Its inference speed is about 1.2 M fuzzy rules per second with 20 MHz frequency.