Robust design and optimization of operating amplifiers

The performance requirements and deadlines in analog IC design are becoming more and more difficult to satisfy. Robust design produces circuits that fullfill the design requirements in several different operating environments and under the influence of manufacturing process variations. Generally designers use computers only for evaluating the circuit. A method based on the robust design process practiced by IC designers is implemented by means of penalty functions and a generic optimization algorithm is used to solve the robust design problem. A designer must provide the circuit topology, the set of optimization parameters with their explicit constraints, the set of dependent parameters, and the set of performance constraints. The method is illustrated with a sample operating amplifier design, which is performed by the computer. The proposed approach is not restricted to amplifiers and can be used to automate the design of other types of circuits as well.