V18AUMLA1210A Datasheet, PDF (3/7 Pages) Littelfuse – Surface Mount Multilayer Varistors (MLVs) AUML Series

Varistor Products
Surface Mount Multilayer Varistors (MLVs) > AUML Series
Temperature Effects
In the leakage region of the AUML suppressor, the device
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and shows a temperature dependent affect. In this region
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at maximum rated voltage are in the microamp range.
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Load Dump Energy Capability
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the automobile is abruptly reduced. The worst case scenario
of this transient occurs when the battery is disconnected
while operating at full rated load. There are a number of
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automotive industry, with the most common one being that
recommended by the Society of Automotive Engineers,
specification #SAE J1113. Because of the diversity of these
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that energy dissipated by the device itself, independent
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handling capability serves as an excellent figure of merit for
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capability requirement is well within the ratings of all of the
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energy, which are applied to the devices. The reliability
information thus generated gives an indication of the
inherent capability of these devices. As an example of
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all cases there has been little or no change in the device
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of the AUML are virtually temperature independent.
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the V-I characteristics of the AUML suppressor.
The very high energy absorption capability of the AUML
suppressor is achieved by means of a highly controlled
manufacturing process. This technology ensures that a
large volume of suppressor material, with an interdigitated
layer construction, is available for energy absorption in an
extremely small package. Unlike equivalent rated Silicon
TVS diodes, the entire AUML device volume is available to
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even energy dissipation ensures that there are lower peak
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AUML suppressor.
There are a number of different size devices available in the
AUML Series, each one with a load dump energy rating,
which is size dependent.
Experience has shown that while the effects of a load dump
tranient is of real concern, its frequency of occurrence is
much less than thoe of low energy inductive spikes. Such
low energy inductive spikes may be generated as a result
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blowing, etc. It is essential that the suppression technology
selected also has the capability to suppress such transients.
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Speed of Response
The clamping action of the AUML suppressor depends
on a conduction mechanism similar to that of other
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slow response time often associated with transient
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parasitic inductance in the package and leads of the
device and less dependent of the basic material (Silicon,
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response time of any suppressor is its lead induc-tance.
The AUML suppressor is a surface mount device, with no
leads or external packaging, and thus, it has virtually zero
inductance. The actual response time of a AUML surge
suppressor is in the 1 to 5 ns range, more than sufficient
for the transients which are likely to be encountered in an
automotive environment.
Figure 5
©2010 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/AUML.html for current information.
Revision: September 14, 2010
Multilayer Internal Construction
AUML Varistor Series