Besides the choice of AC flux density (ΔB) with L_M and N_P, the core loss of the transformer can also be significantly reduced by proper selection of the magnetic core material. For converters operating at full-load switching frequencies up to 250 kHz, ferrite materials such as Ferroxcube 3C97 or 3C98, for example, exhibit low core-loss density. For converters operating at full-load switching frequencies over 400 kHz, materials such as 3F36 from Ferroxcube and N49 from TDK/Epcos exhibit low core-loss density. Other ferrite materials with equivalent or similar loss characteristics may also be used.

Litz wire is recommended for both primary and secondary windings, in order to reduce the R_AC losses caused by high-frequency proximity effect and skin effect of the windings. Choose a suitable insulation class for the windings based on the expected and measured maximum operating temperature under sustained over-stress conditions.