Frequency Optimum of Semiconductor Technologies and State-of-the-Art Magnetic Components on SMPS

Switching frequency is key parameter for SMPS system optimization for efficiency and power density. State-of-the-art power semiconductors allow very high switching frequencies up to the MHz range, especially in the 600/650 V class. Today's limiting factors for overall system frequency are given very often by magnetic materials and components. The paper shows this problematic using the example of transformer and inductor of the well-known two-transistorforward (TTF) converter topology. The difference between an idealised approach and real magnetics designs concerning loss and size reduction with increasing switching frequency is presented.