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: Power supply topologies – Forward of Flyback? Which is Better? Both!

App note from Coilcraft camparing two recognized power supply topologies. Link here (PDF) Beatles or Stones? Michael or LeBron? Deep dish or thin crust? Forward or flyback? These are just a few of the age-old questions that have been hotly debated over the years, people arguing their opinions with great vigor. But, the truth is, […]

App note: Common mode filter inductor analysis

App note from Coilcraft on the design and construction of common mode filter inductor. Link here (PDF) Noise limits set by regulatory agencies make solutions to common mode EMI a necessary consideration in the manufacture and use of electronic equipment. Common mode filters are generally relied upon to suppress line conducted common mode interference. When […]

App note: How current and power relates to losses and temperature rise on inductors and transformers

Coilcraft’s app note on temperature rise due to losses on inductors and transformers. Link here (PDF) Core and winding losses in inductors and transformers cause a temperature rise whenever current flows through a winding. These losses are limited either by the allowed total loss for the application (power budget) or the maximum allowable temperature rise. […]

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: Selecting current sensors and transformers

Selection guidelines from Coilcraft. Link here (PDF) Current sensors detect the flow of AC or DC current in a wire or circuit trace. They can be used to detect an on/off/ pulse current condition or to measure the magnitude of the current in the wire or trace. This discussion is limited to AC current sensors. […]

App note: Transponder coils in an RFID system

A short application note from Coilcraft about transponder coils. Link here (PDF) Radio Frequency Identification (RFID) is the system of using radio signals to send information identifying a particular situation or item. It can be used to track and locate any item including material, people and animals. The RFID transponder coil is part of the […]

App note: Signal transformer application and specification

Application note from Coilcraft discussing the wideband transformer and the autotransformer. Link here (PDF) In the simplest sense, a transformer is two or more windings coupled by a common magnetic field. This magnetic field provides the means to pass voltages and currents from one winding (primary) to the other winding (secondary). Magnetic flux is created […]

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.