Littelfuse SM7 User Manual
Varistor Products
Surface Mount Varistors > SM7 Series
SM7 Varistor Series
Agency Approvals
Agency Agency File Number
E320116
RoHS
Description
The Littelfuse SM7 Series is a plastic-encapsulated
surface-mount metal oxide varistor (MOV) transient
voltage surge suppressor that is designed to be
operated continuously across AC power lines.
The series comprises a Nylon molded package with
tin plated lead frame for soldering to board. The
surface mount SM7 Series is based on radial 7mm
internal varistor element with similar characteristics
to the Littelfuse LA / ZA series of varistor.
Features
• Electrical equivalent
to leaded types
LA/ZA series
• AC Voltage Rating
115 to 510VAC rms
• Good solderability
• Available in tape
and reel
• Application of AC
power meters
• No De-Rating up
to 85°C ambient
SM7 Series
Absolute Maximum Ratings
• For ratings of individual members of a series, see Device Ratings and Specifications chart
Continuous
Steady State Applied Voltage:
AC Voltage Range (V
DC Voltage Range (V
) 115 to 510 V
M(AC)RMS
) 153 to 675 V
M(DC)
Transients:
Peak Pulse Current (ITM)
For 8/20μs Current Wave (See Figure 2) 1200 A
Single Pulse Energy Range
For 10/1000μs Current Wave (W
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 1000 MΩ
STG
V
) of Clamping Voltage (VC) at Specified Test Current <0.01 %/OC
) -40 to +85
A
) -55 to +125
) 10 to 40 J
TM
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.
SM7 Series Units
O
C
O
C
2500 V
© 2013 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/sm7.html for current information.
75
Revised: May 8, 2013
SM7 Series Varistor
Varistor Products
Surface Mount Varistors > SM7 Series
SM7 Series Ratings & Specifications
Maximum Rating (85°C) Specifications (25°C)
Maximum
Clamping
Voltage
8 x 20 μs
IPK C
C
Capacitance
Part
Number
Continuous Transient
V
RMS
V
M(AC)
V
V
M(DC)
DC
Energy
10 x 1000μs
WTM I
Peak Current
8 x 20μs
V
TM
(V) (V) (J) (A) (V) (V) (V) (A) (pF)
Varistor Voltage
at 1mA DC
Test Current
Min V
NOM
NOM
Max V
V115SM7 115 153 10 1200 162 198 300 10 200
V130SM7 130 175 11 1200 184 228 340 10 180
V140SM7 140 180 12 1200 198 242 360 10 160
V150SM7 150 200 13 1200 212 268 395 10 150
V175SM7 175 225 15 1200 247 303 455 10 130
V230SM7 230 300 20 1200 324 396 595 10 100
V250SM7 250 330 21 1200 354 429 650 10 90
V275SM7 275 369 23 1200 389 473 710 10 80
V300SM7 300 405 25 1200 420 517 775 10 70
V320SM7 320 420 25 1200 462 565 850 10 65
V385SM7 385 505 27 1200 558 682 1025 10 60
V420SM7 420 560 30 1200 610 748 1120 10 55
V460SM7 460 615 37 1200 640 790 1190 10 55
V480SM7 480 640 35 1200 670 825 1240 10 50
V510SM7 510 675 40 1200 735 910 1200 10 45
NOTE: SM7 series devices are recognized under UL file # E320116
Typical
f = 1MHz
SM7 Series Varistor
76
Revised: May 8, 2013
Please refer to www.littelfuse.com/series/sm7.html for current information.
Specifications are subject to change without notice.
© 2013 Littelfuse, Inc.
Loading...