Multilayer varistors (MLVs)
Automotive series
Cautions and warnings
General
Some parts of this publication contain statements about the suitability of our ceramic transient
voltage suppressor (CTVS) components (multilayer varistors (MLVs), CeraDiodes, ESD/EMI fil-
ters, SMD disk varistors (CU types), leaded transient voltage/ RFI suppressors (SHCV types)) for
certain areas of application, including recommendations about incorporation/design-in of these
products into customer applications. The statements are based on our knowledge of typical re-
quirements often made of our CTVS devices in the particular areas. We nevertheless expressly
point out that such statements cannot be regarded as binding statements about the suitability of
our CTVS components for a particular customer application. As a rule, EPCOS is either unfamiliar
with individual customer applications or less familiar with them than the customers themselves.
For these reasons, it is always incumbent on the customer to check and decide whether the
CTVS devices with the properties described in the product specification are suitable for use in a
particular customer application.
Do not use EPCOS CTVS components for purposes not identified in our specifications,
application notes and data books.
Ensure the suitability of a CTVS in particular by testing it for reliability during design-in. Always
evaluate a CTVS component under worst-case conditions.
Pay special attention to the reliability of CTVS devices intended for use in safety-critical
applications (e.g. medical equipment, automotive, spacecraft, nuclear power plant).
Design notes
Always connect a CTVS in parallel with the electronic circuit to be protected.
Consider maximum rated power dissipation if a CTVS has insufficient time to cool down
between a number of pulses occurring within a specified isolated time period. Ensure that
electrical characteristics do not degrade.
Consider derating at higher operating temperatures. Choose the highest voltage class
compatible with derating at higher temperatures.
Surge currents beyond specified values will puncture a CTVS. In extreme cases a CTVS will
burst.
If steep surge current edges are to be expected, make sure your design is as low-inductance
as possible.
In some cases the malfunctioning of passive electronic components or failure before the end of
their service life cannot be completely ruled out in the current state of the art, even if they are
operated as specified. In applications requiring a very high level of operational safety and
especially when the malfunction or failure of a passive electronic component could endanger
human life or health (e.g. in accident prevention, life-saving systems, or automotive battery line
applications such as clamp 30), ensure by suitable design of the application or other measures
(e.g. installation of protective circuitry or redundancy) that no injury or damage is sustained by
third parties in the event of such a malfunction or failure. Only use CTVS components from the
automotive series in safety-relevant applications.
Specified values only apply to CTVS components that have not been subject to prior electrical,
mechanical or thermal damage. The use of CTVS devices in line-to-ground applications is
Please read Cautions and warnings and
Important notes at the end of this document.
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