What Are Inductors and Their Common Types?

Whether an electronic circuit is used to power a simple calculator or advanced server systems, many of the same basic building block components are used to construct such assemblies. Across all circuits, the resistor, capacitor, and inductor are the most widely used components, each of which serve varying roles. While resistors manage and control the flow of current, capacitors are capable of storing electrical energy within an electric field as a passive component. Inductors, on the other hand, are quite similar to capacitors, albeit storing energy within a magnetic field. In this blog, we will discuss inductors in more detail, allowing you to better understand their design and use within electronic circuitry.

As stated before, inductors are a type of electronic component that is able to store energy within a magnetic field. With such abilities, an inductor can serve to resist changes in current that occur within a circuit. There are many types of inductors that one may use, each being optimal for varying applications. Some come in different form factors, those being high-frequency inductors, low-frequency power line inductors, and those constructed for decoupling and filtration needs. To help you best understand the various options that one has when procuring inductors, we will discuss some common types.

The laminated core inductor is one that contains a bobbin, laminated core, and a coil that is wrapped around the bobbin. In order to mitigate hysteresis and eddy current losses, laminated core inductors will utilize steel and silicon plates which are placed inside the bobbin inductor element to establish the core. With their inductance and filtration capabilities, laminated core inductors find use within the onboard chargers of electric vehicles, line and noise filters, and CH and CL filter chokes.

The air core inductor is another common type, those of which are constructed by wrapping a length of wire around a cylindrical material to establish the component’s shape. The inductor is then dipped in varnish or secured with wax to retain the shape. With air as their core, air core inductors exhibit low permeability which makes them optimal for high-frequency applications. Generally, air core inductor components are implemented within snubber circuits, TV and radio receivers, filter circuits, and RF tuning coils.

To create a ferrite conductor, one simply needs to wind a length of wire around a ferrite core. Generally, such components exhibit high permeability, ample electrical resistivity, and low eddy current losses. As a result of its design, the ferrite core inductor is quite beneficial for high-frequency applications such as within switching circuits and PI filters.

The bobbin inductor is another choice, those of which feature a cylindrical bobbin made from a wound length of wire that is encapsulated with a shrink tube. As their core material is ferrite, they share certain properties with the ferrite core inductor. They are also small; thus, they can be beneficial for power adapter applications, often being found within SMPS circuits, input and output filters, and PI filters.

When two wires are wound around a common core, a coupled inductor is created. These windings may be connected in various ways based on the needs of the applications, and common configurations include connecting the windings in series, parallel, or as a transformer. For their functionality, coupled inductors transfer energy between windings with mutual inductance, and they are often utilized within DC-DC converters such as the flyback, SEPIC, and cuk converter.

The last type of inductor that we will discuss is the shielded variable inductor, and such components are constructed by wrapping a length of wire around a hollow cylinder bobbin before placing the core. The core of a shielded variable inductor can either be ferrite or brass, ferrite cores work to increase inductance while brass cores decrease inductance. With their design and capabilities, shielded variable inductors commonly find installation within automotive assemblies and are AEC-Q200 compliant.

Beyond such examples, one may also take advantage of multilayer chip inductors, wireless charging coils, shielded surface mount inductors, axial inductors, and other various types. AFR Enterprises is a leading supplier of inductors with new, used, obsolete, and hard-to-find components readily available for purchase with unmatched pricing and rapid lead-times. With AS9120B, ISO 9001:2015, and FAA  AC 0056B certification and accreditation, we go above and beyond industry standards to ensure that customers receive high-quality, dependable items with every purchase. Get in contact with a representative today and see how AFR Enterprises can serve as your strategic sourcing partner for all your operational needs.