Ferrite Core

Also found in: Dictionary, Wikipedia.
Related to Ferrite Core: Ferrite core memory

ferrite core

[′fe‚rīt ′kȯr]
A magnetic core made of ferrite material. Also known as dust core; powdered-iron core.

Ferrite Core


a magnetic flux bar made of ferrite. The ferrites used exhibit a very low specific electric conductivity; thus, for all practical purposes eddy currents do not appear during magnetic reversal, which eliminates energy losses. As a result, ferrite cores can be used in electronic equipment operating in the radio-frequency range. The primary areas of application for ferrite cores are radio engineering, automation, telemechanics, and computer technology.

Production technology for the manufacture of ferrite cores is based on the techniques of powder metallurgy. Cores of a required shape are compressed from a mixture of powders, and the material is sintered at a temperature of 850°–1500°C in air and then slowly cooled for several hours. The magnetic and dielectric properties of a ferrite core depend on the composition of the mixture, the percentage content of the base components, and the process of heat treatment used. By altering these factors, it is possible to obtain ferrite cores with various required properties, for example, with a high initial magnetic permeability, for use in high-frequency and pulse transformers, or with a rectangular magnetic hysteresis loop, for use in memories.

The techniques of powder metallurgy make it possible to manufacture ferrite cores in various shapes (U-shaped, E-shaped, ring-shaped, and pot cores and complex configurations with several openings on one or several planes) and in a variety of sizes (from tenths of a millimeter to several centimeters). Ring cores that exhibit rectangular hysteresis loops are the most common type. After magnetization and removal of the magnetized field, they can preserve indefinitely one of two possible stable magnetic states, corresponding to the two values of residual magnetic induction (+ Br and –Br). This property makes them suitable for use as elements in memories and logic devices, for example, diode and transistor ferrite storage cells.

Magnetic reversal of the ferrite core, that is, the shift from one magnetic state to another, is caused by the magnetic field of an electric current in the windings of the ferrite core. The time required for magnetic reversal depends on the amplitude and shape of the pulse current, the coercive force, the rectangularity of the hysteresis loop, and the geometric dimensions of the core; it ranges from tenths of a microsecond to several microseconds. Ring ferrite cores with nonrectangular hysteresis loops are primarily used in pulse transformers and high-frequency choke coils.


Pirogov, A. I., and Iu. M. Shamaev. Magnitnye serdechniki dlia ustroistv avtomatiki i vychislitel’noi tekhniki, 3rd ed. Moscow, 1973.
Bardizh, V. V. Magnitnye elementy tsifrovykh vychislitel’nykh mashin, 2nd ed. Moscow, 1974.


References in periodicals archive ?
Tokyo, Oct 14, 2009 - (ACN Newswire) - The invention of ferrite by the Tokyo Institute of Technology and the commercial development of ferrite cores by TDK made substantial contributions to the global electronics industry.
These inductors use a ferrite core material which yields a 90% core loss reduction and 30% increase in maximum operating temperature when compared to standard iron powder material used in flat-coil inductors.
Tenders are invited for Ferrite Core For Bur-1/2 As Per Specn No-Clw/Es/3/0431
The dual-staple inductor design lowers direct current resistance (DCR), and the low-loss ferrite core reduces inductor switching losses.
Tenders are invited for Supply of Ferrite Core Transformer
Pulse's PG0702NL series uses a ferrite core material which has one tenth the core loss of iron powder or iron alloy core materials.
A compact ferrite core made from high saturation, low loss material is being utilized by this inductor design series.
Pulse's PA1894NL and PA2080NL series use a single-turn conductor with a ferrite core instead of a multi-turn conductor wound on a powdered iron toroid core.
Both GIGABYTE Classic Contest prizes feature the latest GIGABYTE Ultra Durable 5 technology which includes high current capable components for the CPU power zone including IR3550 PowIRstageA ICs from International Rectifier, 2X Copper PCB and high current Ferrite Core Chokes rated up to 60A, which together are able to deliver up to 60AC cooler temperatures than traditional motherboards.
These inductors use a power ferrite core material which results in 10 times lower core losses than iron powder or iron alloy cores while maintaining the same saturation current as 4040 iron powder inductors.
While today we re proud to offer our customers the exceptional durability of our Ultra Durable 5 technology, it s been a long road that has seen us adopt several exclusive features including DualBIOS , Lower RDS(on) MSOFETs, Ferrite Core chokes, 2x Copper PCB as well as High Temperature, Humidity, Electrostatic and Power Failure protection technologies.
It breaks down demand for inductorsinto the EMC suppression markets, the chip coil markets for signal decoupling, the wirewoundinductors for power and the unique ferrite core markets.