AN021

AN021 A Handy Method to Obtain Satisfactory Response of Buck Converter Introduction The focus of this application note is to help users to select a good set of components of the compensation section of the Buck converter. Traditionally, engineers first concern about the power circuit for a circuit design. After meeting the power requirement, what follows is control loop design. The first priority of control design is the stability. And after that, the choice of components can substantially effect the transient response. Here shows a simple method to obtain a satisfactory transient response with an acceptable steady state error. Analysis: Fig.1 shows the unity feedback system for Buck converter. We first identify transfer functions for each of the corresponding block. As to the modeling of the low-frequency behavior of power switches in square-wave power converters, please refer to appendix [1]. The circuit of Buck converter is shown in Fig.2 and the model of its power switches is sho...