Fuzzy Logic Based Guidance to Graph Grammar Framework for Automated Analog Circuit Design

This paper introduces a fuzzy logic based guidance architecture to a graph grammar framework for automated design of analog circuits. The grammar generates circuit topologies through a derivation tree. To boost this tree based synthesis mechanism, smaller building blocks in the form of subtrees have been used for the purpose. These blocks have been automatically generated and their appropriateness for the design is updated runtime through the fuzzy system. Fuzzy logic helps to provide a smooth gradation for the relative merit of each block with respect to the design synthesized. The tool has been used to design an operational amplifier and a voltage controlled oscillator.