Abstract
A transformer possesses several functions, such as insulation, voltage transformation, impedance transformation, and so forth. Similarly, an inductor or a reactor is used for current ripple reduction, resonance, energy storage, and so on. Those magnetic power devices are separately placed and connected to circuitries so far. On the other hand, cost reduction is strongly required in designing power supplies. Therefore, power circuit engineers always consider the ways to reduce the number of circuitries.
In this article, we introduce recently developed technologies that reduce the number of circuitries in DC-DC converters by synthesizing the functions of a transformer and an inductor.