L.1.5 Core materials and their losses Introducing solids into a magnetic field, their behaviour can be classified in three groups: diamagnetic materials paramagnetic materials ferromagnetic materials Diamagnetic and paramagnetic materials have a relative permeability close to one. They are therefore only of limited suitability in the construction of inductive components. Ferromagnetic materials have a relative permeability between 10 and 100 000. In order to...

L.1.2 Magnetic induction B A potential is induced in a conductor loop if the magnetic field passing through the conductor loop changes with time. Featured Image Fig. 1.10: Experimental configuration for magnetic induction The surge in potential over the area of the loop is known as the magnetic induction B. Like the magnetic field strength, the magnetic induction B is a vector quantity. The...

C1.3 LOSSES C 1.3.1 Impedance and ESR A capacitor creates in AC circuits a resistance, the capacitive reactance (Formula C1-3). There is also certain inductance in the capacitor. In AC circuits it produces an inductive reactance that tries to neutralize the capacitive one. Finally the capacitor has resistive losses. Together these three elements produce the impedance, Z. If we apply an AC voltage over...

C1.2 INSULATION RESISTANCE, IR  Figure C1-10. Schematic of the Insulation Resistance IR in a capacitor The dielectric of a capacitor has a large area and a short length. Even if the material is a good isolator there always flows a certain current between the charged electrodes (the current increases exponentially with the temperature). This leakage can be described as a parallel resistance with a...

C1.1 CAPACITANCE The Capacitance is determined by, among other things, the characteristics of the dielectric material. International standards speak of the Dielectric Constant or permittivity, designated by the symbol ε. C1.1.1 Description A capacitor serves as a reservoir for electric charges. The size of the ”reservoir” is called capacitance and is expressed in the quantity F(arad) or As/V. The principle Figure C1-1 shows how...

L.1 Basic principles of inductive components Magnetism The basis for understanding inductors is provided by magnetism and a few fundamental electromagnetic field laws, revealing clear and fundamental knowledge of inductorsand ferrites. The most important phenomena and laws will still perhaps be there from physics lessons: Featured Image Fig. 1.1: Bar magnet Every magnet has a north and south pole (The earth is an enormous...

The aim of this survey is to collect and summarise mounting recommendations of publicly available information from capacitor and resistor commercial component manufacturers. The survey aim is to collect the manufacturer’s recommendations and good tips for capacitors and resistor mounting BEYOND the industry standards. The survey doesn’t aim to provide a complete mounting procedure guidelines as part of specific industrial requirement and standards. Capacitor...

The following is a list of most common soldering and mounting standards used and referred by passive component manufacturers in their mounting guide specifications:   EIA/IPC/JEDEC J-STD-002E - Solderability Tests for Component Leads, Terminations, Lugs, Terminals and Wires JESD22-B102E - Solderability IPC/JEDEC J-STD-020E - Moisture/Reflow Sensitivity Classification for Non-Hermetic Solid State Surface Mount Devices IPC/JEDEC J-STD-033C- Handling, Packing, Shipping and Use of Moisture/Reflow Sensitive...

IR reflow soldering IR infrared “convection” reflow is commonly used in commercial large volume SMD components mounting process. The main differences in reflow soldering processes and oven types lie in heat transfer methods - radiation, conduction, convection and condensation. In fact, all heat transfers are used in modern reflow ovens. The heat is applied from above, below, or all directions dependent on the equipment...

Oxidization Fast oxidisation is a common issue related to high temperatures and presence of oxygen during the convection reflow or wave soldering processes. The oxidisation may induce some degradation of metal surface and its environmental robustness, thus impacting the components and the electronic hardware lifetime. The level of oxidisation is depending on more factors, the second most important (after the degree of temperature itself)...