Size and cost reduction of the energy-storage capacitors

In order to feed a VRM from the AC line, several voltage-reduction steps are used. In this power chain, energy storage is required. This paper pretends to select the best voltage to store the energy and also to select the point in which to place the storage capacitor, looking for a reduction of the size and cost of this capacitor. To comply with this aim, two configurations of the power chain have been compared as well as different output voltages for each power block. The proposed analysis has resulted in some practical recommendations about how to handle the main factors, which determine the size and cost of the storage capacitors.