Design Oriented Analysis of Switched Capacitor DC–DC Converters

A novel approach to the design of switched capacitor (SC) converters is presented in this article. By recognizing the relationship between three design parameters in SC converters, namely capacitance, switching frequency, and switch on-resistance, this work is able to align the design method of SC more closely with conventional power converters. Using the charge-multiplier framework for design, capacitor sizes can be related to one another and subsequently to output voltage ripple, a key design parameter of converters. Optimization tools are used to take the equations developed for hand calculation and enable a more broad generalization of how SC converters can be designed. Typically it is thought that the larger the voltage ripple in SC converters is, the less efficient the converter is. However, this design method shows that this is not necessarily the case. Experimental prototypes are designed with these tools to show the validity of the proposed method.