Amplifier design for fast settling performance

A design strategy for minimizing a feedback amplifier's step-response settling time is introduced. Central to this approach is the clear identification of the independent design parameters characterizing the amplifier and the introduction of a figure of merit for assessing the settling performance of an amplifier that is independent of power, supply voltage and capacitive loading. With this approach, the settling performance of a given amplifier architecture can be optimized and the relative performance of different amplifier architectures can be assessed. Emphasis in this paper is on the two-stage operational amplifier architecture but the technique readily extends to other widely used operational amplifier structures.