Computer aided design of analog circuits
Nobuo Fujii · 2005
Summary form only given, as follows. The complete presentation was not made available for publication as part of the conference proceedings. This talk presents an automatic synthesis of analog circuits that uses evolutionary search and employs some topological features of analog integrated circuits. Firstly, the system randomly generates a set of circuits, and then evolves their topologies and device sizing to fit an environment that is formed by the fitness function translated from the electrical specifications of the circuit, Thus expert knowledge about circuit topologies and sizing are not needed. Though the circuits can be automaticalIy generated by the above method, the designed circuits sometimes are quite complicated and have many strange structures. In addition, it takes a long cakulation time. These are resulted from that the method does not utilize any analog circuit design knowledge. If we can use the knowledge of analog circuit designers, we can extremely save the design time and area of integrated circuits. In order to include the design knowledge, we reuse the topological features of prototype circuits that have been designed by humans. The information about the circuit connections is extracted from the prototype circuits and stored in a data base as sub-circuits. The genetic algorithm searches an optimum combination of the sub-circuits that meet the given specifications. Some design examples will be given to show the ability of the analog CAD.