Design Optimization Methodology for CMOS Operational Amplifier Using NSGAII

Abstract

This paper focuses on the synthesis and design of CMOS operational amplifiers (op amps) using novel multi objective algorithm. The synthesis of CMOS op-amps can be translated into a multiple-objective optimization task, in which a large number of specifications have to be taken into account, i.e., area, power consumption, slew rate and gain-bandwidth. A multi-objective algorithm called elitist non-dominated sorting genetic algorithm (NSGA-II) is applied to search for multiple optimal solutions, which includes transistor sizes, bias currents and compensating capacitance values. The knowledge of this helps the designer to compare and choose a compromised optimal solution for automating the operational amplifier design. The proposed methodology has the ability to generate in short times constraint satisfying solutions The algorithm is implemented in C programming language and PSICE is used to evaluate the required circuit parameters The simulation results confirms the efficiency of the NSGA-II algorithm in determining the device sizes.