ferrite core

One of the cores widely used in transformers and choke coils for switching power supplies. The most commonly used type of ferrite is spinel ferrite, represented by the molecular formula MO·Fe2O3 (where M is a divalent metal). Spinel ferrite cores are manufactured by placing metal oxide powder into a mold, compressing it, and then firing it. To increase the saturation magnetic flux density, spinel ferrite is often made by mixing multiple metal materials and is therefore called composite ferrite.

Ferrite cores have the advantage of low iron loss even when there are large changes in magnetic flux density in high-frequency regions, making them suitable for output transformers and transformers with large current fluctuations. On the other hand, they have the disadvantage of lower saturation magnetic flux density compared to metal cores.

In addition, the core attached to the DC cord of an AC/DC Power Adapters — Desktop & Wall-Mount as an EMI countermeasure (noise suppression) is also called a ferrite core.