Automatic design of operational amplifier by combination method of function block

In this paper, we studied the automated design of analog circuit. Automated design technique of analog circuit has not been established. Auto design has already been positively used in the digital circuit. The difference between the design time has become a bottleneck of the integrated circuit development. Several studies have also been made in the past [1]-[3]. However, they are not practical. Because, made circuit can't be understood by people, or circuit can't be designed. In this paper, I had verified the technique of automatic design, in order to shorten the design time of the analog circuit. Circuit is reliably designed, and yet the designed circuit is understandable. First of all, we decided to automated design an important circuit block of the analog circuit. This time, we decided to design object an operational amplifier because it is widely used in mobile terminal and radio device. Using a genetic algorithm, it is a learning algorithm that mimics the process of evolution going organisms to adapt to the environment. Replacing the minimum design conditions of the operational amplifier to the environment, we evaluated the degree of evolution. Design conditions the following circuit is discarded, high evaluation value circuit will survive to the next generation. Finally we discussed the validity of the finally designed circuit and the study.