App note: Power inductors 101

App note from Vishay about how modern power inductors are made and their performance. Link here (PDF) Power inductors are typically used for energy storage in DC/DC converters or high current noise filter applications, including motor speed control, adjustable lighting, DC power conditioning, and more. Power inductors can be divided further into two groups – […]

App note: Inductors as RF chokes

App note from Coilcraft on how inductors where used for solving RF isolation issues. Link here (PDF) Many consumer products communicate with each other over broadband networks. From television to fiber transmission networks, the bandwidth of data communication is increasing, and the integrity of RF signals has become a major design concern. This paper provides […]

App note: Measuring self resonant frequency

App note from Coilcraft on determining the self resonant of an inductor and how to compare them to other identical inductors. Link here (PDF) When comparing published electrical values, engineers require a common basis for comparison. Ideally, a 100 nH inductor with a self resonant frequency (SRF) of 1 GHz from one manufacturer is equivalent […]

App note: Power-handling capabilities of inductors

App note from Coilcraft on how to calculate the power dissipation of an inductor. Link here (PDF) Inductors are not typically rated by power, however an approximation of the power-handling capability of an air core or ceramic core chip inductor can be estimated using the data sheet specifications for current and resistance.

App note: Operating voltage ratings for inductors

Coilcraft’s app note on why inductor’s voltage ratings are uncommonly mentioned in most applications. Link here (PDF) Voltage ratings are often specified for many electronic components, including capacitors, resistors and integrated circuits, but traditionally this has been rare for inductors. Recent trends, particularly the introduction of higher voltage rated semiconductor devices, have created a new […]

App note: Selecting coupled inductors for SEPIC applications

Application example from Coilcraft on how coupled inductors gain advantage over separately wound inductors, calculations included. Link here (PDF) The SEPIC (Single-Ended Primary Inductance Converter) topology is used in applications that require characteristics of both a buck and a boost regulator, specifically the ability to step up and step down the input voltage. Most often […]

App note: Choosing inductors for energy efficient power applications

Designing efficient power converters guide from Coilcraft. Link here (PDF) In high frequency DC-DC converters, inductors filter out the AC ripple current superimposed on the DC output. Whether the converter steps the voltage down – buck – or steps the voltage up – boost – or both up and down – SEPIC, the inductor smooths […]

App note: Testing inductors at application frequencies

An app note from Coilcraft on inductance and Q parameters which are the important factors of an inductor and how these values are found. Link here (PDF) The accurate measurement of an inductor has always been more difficult than the measurement of other passive components. The primary difficulty with coil measurements lies in the fact […]

App note: Working voltage ratings applied to inductors

Coilcraft’s application note about why there are no voltage ratings specified on inductors. Link here (PDF) Voltage ratings are often specified for many electronic components, including capacitors, resistors and integrated circuits, but rarely for inductors. This article addresses the reasons why working voltage ratings are not typically published for inductors. There are challenges to determine […]

App note: Inductor performance in high frequency DC-DC converters

Coilcraft’s application note on inductor performance or efficiency when used in high frequency applications. Link here (PDF) ESR vs frequency curves can be used to predict inductor losses in higher frequency converters, but careful consideration must be given to the wave shape (ripple current) of each application.

App note: Cracks on molded power inductors

App note from Würth Elektronik on WE-LHMI inductors’ visual crack apperance and their effects. This document helps understanding the influence of visual asymmetry around the core which may occur during the manufacturing process of WE-LHMI series inductors. The WE-LHMI core is not a solid core, instead it is an iron powder molded around the winding. […]