Multi-objective Evolutionary Design and Knowledge Discovery of Logic Circuits with an Improved Genetic Algorithm

Abstract

To improve evolutionary design of circuits in efficiency, scalability and optimizing capability, a genetic algorithm based approach was proposed. It employs a gate-level encoding scheme supporting flexible changes of functions and interconnections of comprised logic cells, a multi-objective evaluation mechanism of fitness with weight-vector adaptation and circuit simulation, and an adaptation strategy for crossover probability and mutation probability to vary with individuals’ diversity and genetic-search process. It was validated by experiments on arithmetic circuits, obtaining circuits with expected functions, novel structures, and higher performances in gate usage and operating speed as compared with the results of both conventional and evolutionary approaches. Moreover, by studying the circuits evolved for problems of increasing scales, some novel, efficient and generalized principles have been discerned, which are easy to verify but difficult to dig out by human experts with existing knowledge.