Component characterization and constraint transformation based on directed intervals for analog synthesis

In this paper, we present a technique for characterizing CMOS analog circuits based on directed intervals. The technique consists of an analog performance estimator and a characterization table generator. This characterization information may be efficiently used by the constraint transformation step in an analog synthesis system. We present a genetic algorithm based constraint transformation method, that exploits problem structure by using the circuit characterization information. We discuss the design of the genetic operators that capture the characteristics of the constraint transformation problem. The constraint transformation method that uses the characterization information was compared against one using a conventional genetic algorithm and the experimental results obtained demonstrate the effectiveness of the proposed approach.