A method for estimating switch-mode power supply size

A method of estimating the physical size and layout of switch-mode power supplies is presented. This method includes analytical expressions for determining the physical size of inductors, capacitors, and transformers. The calculations are based on the black box input-output requirements of the power supply, and can be used to evaluate and compare competing design approaches or topologies. The technique is based on fundamental power supply parameters-power, energy, and electric charge-and avoids needless calculations during the initial estimation stage of a power supply design. Calculations using this estimation technique are presented for buck, forward flyback, and boost regulators