Power Inductors
What is a Power Inductor?
Power Inductors are used in virtually every electronic system and every market segment from small sub-watt wearable and hand-held devices to large kilowatt and megawatt industrial power installations. They can be used in a variety of functions including differential mode filtering, output chokes and as the main energy storage device in multiple power supply topologies.
A coil is a generic name for an electrode in the shape of a spiral. Among the different types of coils, there are coils called “inductors” which are used for electrical applications. Inductors can be further categorized into RF inductors used for signal processing, and power inductors for power supply lines. The power inductors discussed in this section form part of the voltage conversion circuit in a DC-DC converter or other device.
Here we will explain the operation of a power inductor in a DC-DC converter. A power inductor is used in a step-up, step-down, or step-up/step-down circuit to convert a certain voltage to the required voltage. Among those different circuits, it is primarily used in a type of circuit called a “switching regulator.”
It uses an IC, power inductor, and capacitor to convert a DC input voltage to the required output voltage. The power inductor works with the capacitor to play the role of rectifying the rectangular wave output from the IC to a direct current.
If either one of these components is missing, the output cannot be properly rectified.
Power inductor selection issues
- Inductance value which will be based on the requirements of the circuit application.
- Current rating to ensure the part will not overheat and that is is compatible with the circuit requirements.
- Saturation current to ensure the component will not saturate at peak application current.
- AC core and AC conductor loss calculation to verify thermals and efficiency.
Pulse Power Inductors come in a wide-range of product technologies including power beads, molded, composite, round wire coils, drum cores, flat wire, planar and toroids. Offerings range from a few mA to 150Apk, from 20nH to 10mH in both surface mount and through-hole configurations