• For ratings of individual members of a series, see Device Ratings and Specifications chart
©2010 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/sm20.html for current information.
Steady State Applied Voltage:
Transients:
Operating Ambient Temperature Range (T
Storage Temperature Range (T
Temperature Coefficient (a
Hi-Pot Encapsulation (COATING Isolation Voltage Capability)
(Dielectric must withstand indicated DC voltage for one minute per MIL-STD 202, Method 301)
COATING Insulation Resistance
Agency Approvals
Absolute Maximum Ratings
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only
rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is
not implied.
Continuous
Agency
AC Voltage Range (V
DC Voltage Range (V
Peak Pulse Current (I
Single Pulse Energy Capability (W
Load Dump Energy Capability (td>=30ms)
SM20 Varistor Series
V
) of Clamping Voltage (V
STG
M(AC)RMS
M(DC)
TM
)
) 8/20μs Current Wave, Single Pulse
Agency File Number
)
)
E320116
A
)
TM
) 10/1000μs Current Wave
C
) at Specified Test Current
Varistor Products
Surface Mount Varistors > SM20 Series
Revision: May 11, 2010
Description
The Littelfuse 20mm SMD Series is a surface-mount
metal oxide varistor device, for use in applications
requiring hi-energy / transient current capability.
The AC rated parts are designed to operate
continuously across AC power lines. The DC rated
parts are suitable for Automotive applications. The
series comprises a Nylon molded package with folded
tin plated metal leads for soldering to board.
The SMD Series is based on radial 20mm internal
varistor element with similar characteristics to
the Littelfuse LA / ZA series of varistors.
Features
•
•
•
•
DC Voltage
Rating 26VDC
AC Voltage Rating
175 - 320AC
No De-Rating up
to 85°C ambient
Lead-Free, Halogen-
Free and RoHS
Compliant
SM20 Series
-55 to +125
up to 6500
-40 to +85
20 to 320
<0.01
2500
1000
165
160
26
Units
%/
MΩ
O
O
V
V
A
V
J
J
C
C
O
•
•
C
Low voltage
devices specified
for automotive load
dump energy
Available in "waffle"
tray packaging
SM20 Series Varistor