Cascade Connection of the Ladder Switched Capacitor Cell

Abstract

This work presents an alternative for the connection of switched capacitor ladder cells in order to obtain a high cc-cc conversion rate. The proposed modification consists in split the output capacitor of the first cell, being they the input capacitors of a second ladder cell, that is, a series connection with integration of elements is performed. The modification in the output capacitor allows the connection with a reduced number of components. These advantages make the structure suitable for converters with a high conversion rate, step-up or step-down. The topology, the ladder cell and connection analysis, the equivalent circuit and cascade connection loss analysis are studied. The theoretical analysis is validated through experimental results in a prototype of 200 V for 50 V and 200 W of power. Additionally, a comparison with the classic ladder connection and other high-gain converters is presented to highlight the advantages and disadvantages of the proposed structure.