R 22.1/13.7/7.9 B64290A0719X049
Ferrite core B64290
2017-08-29
Please read Cautions and warnings and Page 3 of 5
Important notes at the end of this document.
Cautions and warnings
Mechanical stress and mounting
Ferrite cores have to meet mechanical requirements during assembling and for a growing number of
applications. Since ferrites are ceramic materials one has to be aware of the special behavior under
mechanical load.
As valid for any ceramic material, ferrite cores are brittle and sensitive to any shock, fast temperature
changing or tensile load. Especially high cooling rates under ultrasonic cleaning and high static or
cyclic loads can cause cracks or failure of the ferrite cores.
For detailed information see data book, chapter “General - Definitions, 8.1”.
Effects of core combination on AL 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, chapter “General - Definitions, 8.1”.
Heating up
Ferrites can run hot during operation at higher flux densities and higher frequencies.
NiZn-materials
The magnetic properties of NiZn-materials can change irreversible in high magnetic fields.
Ferrite Accessories
EPCOS ferrite accessories have been designed and evaluated only in combination with EPCOS
ferrite cores. EPCOS explicitly points out that EPCOS ferrite accessories or EPCOS ferrite cores may
not be compatible with those of other manufacturers. Any such combination requires prior testing by
the customer and will be at the customer‘s own risk.
EPCOS assumes no warranty or reliability for the combination of EPCOS ferrite accessories with
cores and other accessories from any other manufacturer.
Processing remarks
The start of the winding process should be soft. Else the flanges may be destroyed.
– Too strong winding forces may blast the flanges or squeeze the tube that the cores can not be
mounted any more.
– Too long soldering time at high temperature (>300 °C) may effect coplanarity or pin arrangement.
– Not following the processing notes for soldering of the J-leg terminals may cause solderability
problems at the transformer because of pollution with Sn oxyd of the tin bath or burned insulation
of the wire. For detailed information see chapter “Processing notes”, section 2.2.
– The dimensions of the hole arrangement have fixed values and should be understood as a
recommendation for drilling the printed circuit board. For dimensioning the pins, the group of
holes can only be seen under certain conditions, as they fit into the given hole arrangement. To
avoid problems when mounting the transformer, the manufacturing tolerances for positioning the
customers’ drilling process must be considered by increasing the hole diameter.
