N27 Datasheet, PDF (6/7 Pages) EPCOS – Ferrites and accessories

SIFERRIT materials
Cautions and warnings
General
Based on IEC 60401-3, the data specified here are typical data for the material in question, which
have been determined principally on the basis of toroids (ring cores).
The purpose of such characteristic material data is to provide the user with improved means for
comparing different materials.
There is no direct relationship between characteristic material data and the data measured using
other core shapes and/or core sizes made of the same material. In the absence of further agree-
ments with the manufacturer, only those specifications given for the core shape and/or core size in
question are binding.
Effects of core combination on A_L value
Stresses in the core affect not only the mechanical but also the magnetic properties. It is apparent
that the initial permeability is dependent on the stress state of the core. The higher the stresses are
in the core, the lower is the value for the initial permeability. Thus the embedding medium should
have the greatest possible elasticity.
For detailed information see Data Book 2007, chapter “General – Definitions, 8.2”.
Heating up
Ferrites can run hot during operation at higher flux densities and higher frequencies.
6 09/06