Design of two-stage Miller-compensated amplifiers based on an optimized settling model

A new methodology for the design of two-stage Miller-compensated operational amplifiers in closed-loop applications is proposed in this paper. This methodology that is based upon a new fundamental settling-based analysis specifies the proper open-loop parameters of the opamp regarding to its desired closed-loop specifications. As the conventional model for the step settling response of two-stage opamps have always been overestimated, a simple yet accurate settling model is also suggested to optimize the methodology. The proposed methodology is especially helpful in those applications where the settling response is important. Simulation results are presented to show the effectiveness of the design methodology and to compare the proposed model with the conventional model.