Ferrite core is a kind of high-frequency magnetic material (the principle is the same as that of silicon steel sheet, but used in high-frequency environment), mainly used as high-frequency transformer (like switching power supply, line output transformer, etc.), high-frequency magnetic ring (For anti-interference), etc., increase the permeability and improve the quality factor of inductance, which is used in the transformer.
Ferrite cores are mainly composed of iron (Fe), manganese (Mn), and zinc (Zn) 3 metal elements, usually called manganese-zinc ferrite. The toroidal ferrite core has no air gap and the same cross-sectional area, so the magnetic effect is very high.
The ferrite magnetic ring has a lot of specifications and sizes, which can be selected according to the material of the magnetic ring, and different coatings can be used to simplify the winding and increase the breakdown voltage.
Ferrite core is made of dense and homogeneous ceramic structure non-metallic magnetic material, with low coercivity, also known as soft ferrite. It is composed of oxide or carbonate compounds of iron oxide (Fe2O3) and one or more other metals (such as manganese, zinc, nickel, and magnesium). The ferrite raw material is pressed and then sintered at a high temperature of 1300°C, and then machined to produce a finished magnetic core that meets the application requirements. Compared with other types of magnetic materials, the advantage of ferrite is that the magnetic permeability is very high, and It has the advantages of high resistance and low eddy current loss in a wide frequency range. These material properties make ferrite an ideal material for applications such as high-frequency transformers, broadband transformers, adjustable inductors and other high-frequency circuits from 10kHz to 50MHz.
Ferrite cores can be wound with coils to make inductors or transformers. They are widely used in instrumentation, communication equipment and household appliances. Ferrite cores have many material grades and various geometric shapes, including cylindrical, I-shaped, cap-shaped, single-hole, double-hole, four-hole, U-shaped, pot-shaped, E-shaped, EI-shaped, EC-shaped, RM shape, PQ shape, EP shape, see attached picture. Each shape of the magnetic core is self-contained for users to choose from. Ferrite cores have a wide range of choices. Different materials and shapes can be selected according to different magnetic parameters. Due to their low magnetic loss at high frequencies, they are widely used in switch mode power supplies (SMPS) and radio frequency (RF) transformers. And inductors. Ferrite cores of various shapes and sizes are used in inductors, pulse transformers, high-frequency transformers, and noise filters in the high-frequency power supply and high-quality communications markets. The characteristics of ferrite are excellent resistance, good temperature characteristics, and low attenuation rate.
Compared with an air-core coil of the same volume, an inductor made by winding a coil on a ferrite core has a larger inductance and a higher Q value (quality factor). For example, the Gu-22×13 pot-shaped magnetic core, when using it to make a 4mH inductor, it only needs to wind 43 turns of the coil. If the pot-shaped magnetic core is not used, it is changed to an air-cored coil, and 600 turns are needed to obtain the 4mH inductance. Device. It can be seen that after using the magnetic core, the volume of the inductor or transformer can be greatly reduced.