Master the Basics: Types of Inductors
Inductors are fundamental components in electronics, easily recognizable by their coiled wire structure. They are commonly found in power supply circuits and other electronic applications that require energy storage and filtering.
Key Characteristics of Inductors
When selecting an inductor, consider the following specifications:
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Inductance (H) – Measured in Henrys (H), it determines the inductor’s ability to store energy in a magnetic field.
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DC Resistance (DCR) – Represents the resistance of the wire when a constant current flows through it, usually less than 1 ohm.
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Maximum Current Rating – The highest amount of current the inductor can handle before overheating and damaging its coil.
Common Types of Inductors
Inductors come in various shapes and sizes, depending on their application:
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Plated Through-Hole Inductors – Classic coil-shaped components, easily recognizable in circuits.
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Cylindrical Inductors – Resemble electrolytic capacitors, often used in power supply circuits.
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Axial Inductors – Look similar to resistors, with leads extending from both ends.
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Surface-Mount Inductors (SMD) – Compact, rectangular packages ideal for modern electronics and PCB designs.
Core Materials
Most inductors have their wire coils wrapped around a ferromagnetic core (e.g., iron or ferrite) to increase inductance while minimizing size. The core enhances the magnetic field, allowing the inductor to store more energy efficiently.
Combining Inductors
Like resistors and capacitors, inductors can be combined in series or parallel to achieve different inductance values:
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Inductors in Series: The total inductance is the sum of all individual inductances:
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Inductors in Parallel: The total inductance follows the reciprocal formula:
Practical Use
Unlike resistors and capacitors, inductors are less frequently used in basic circuit designs, so many engineers purchase them as needed rather than keeping a large stock. However, a small selection of inductors ranging from microhenrys (µH) to millihenrys (mH) can be useful for quick prototyping.
Key Takeways
Inductors are essential for energy storage, filtering, and signal processing in electronics. Understanding their types, core materials, and combination rules helps in selecting the right inductor for specific applications, ensuring efficient circuit performance.
