SM/ SMX Series — Surface Mount - Wirewound/ Film
Features
SM - Wirewound Element
• High temperature molded encapsulation
• Flex termination for absorbing thermal expansion
• All welded construction
• Available in non-inductive styles
SMX - Metal Oxide Element
• SMX: economical SMT 2 and 3watt
• SMX extends value range up to 470K
• Both are RoHS compliant/ lead-free
Electrical Specifications
Type
Power Rating
(Watts)
@ 70°C
1W
2W
2W
2W
3W
3W
Maximum
Working Voltage
Resistance
Temperature
Coefficient
±100 ppm/°C
± 20 ppm/°C
±100 ppm/°C
± 20 ppm/°C
±200 ppm/°C
±100 ppm/°C
±100 ppm/°C
± 20 ppm/°C
±200 ppm/°C
Ohmic Range and Tolerance
0.1% & 0.5%
0.01Ω – 10Ω*
10Ω – 1K
0.01Ω – 10Ω*
10Ω – 2K
–
0.005Ω – 0.976Ω*
0.01Ω – 10Ω*
10Ω – 3.01K
–
1%
0.01Ω – 10Ω*
10Ω – 1K
0.01Ω – 10Ω*
10Ω – 2K
2.0K – 100K
0.005Ω – 0.976Ω*
0.01Ω – 10Ω*
10Ω – 3.01K
3.01K – 118K
5%
0.01Ω – 10Ω*
10Ω – 1K
0.01Ω – 10Ω*
10Ω – 2K
2.0K – 470K
0.005Ω – 0.976Ω*
0.01Ω – 10Ω*
10Ω – 3.01K
3.01K – 470K
SM 1
SM 2
SMX 2
SM 2A
SM 3
SMX 3
25
50
350
60
100
500
* Zero ohm available on all sizes .
Mechanical Specifications
Type
Tolerance
SM 1
SM/ SMX 2
SM 2A
SM/ SMX 3
A
Body Length
±0.015
±0.4
0.260
6.6
0.410
10.4
0.475
12.1
0.629
16.0
B
Total Length
±0.032
±0.81
0.280
7.1
0.435
11.1
0.500
12.7
0.708
18.0
C
Body Height
±0.015
±0.4
0.140
3.6
0.180
4.6
0.140
3.6
0.256
6.5
D
Body Width
±0.015
±0.4
0.150
3.8
0.240
6.1
0.305
7.8
0.276
7.0
E
F
Termination Width Termination Length Units
±0.015
±0.4
0.090
2.3
0.100
2.5
0.110
2.8
0.110
2.8
±0.015
±0.4
0.100
2.5
0.115
2.9
0.115
2.9
0.115
2.9
inches
mm
inches
mm
inches
mm
inches
mm
How to Order
SM
SEI Type
2
Code
1K
Nominal Resistance
1%
Tolerance
R
Packaging
Type
SM
SMX
Element
Wirewound
Metal Oxide
Code
1
2
2A
3
Size
2815
4424
5031
7128
Tolerance
0.1%
0.5%
1%
5%
Series
SM 1
SM 2, SMX 2
SM 2A
SM 3, SMX 3
Code
R
R
R
R
Description
13" Reel
13" Reel
13" Reel
13" Reel
Pkg Qty
1,500
800
1,200
750
Toll Free: (888) SEI-SEIS
(888) 734-7347
www.seielect.com
45
email: marketing@seielect.com
SM/ SMX Series — Surface Mount - Wirewound/ Film
Performance Characteristics
Test
Moisture Resistance
Thermal Shock
Load Life @70°C – 1,000 hrs.
Shock and Vibration
Resistance to Soldering Heat
Terminal Strength
Dielectric Withstanding Voltage
Short Time Overload
Low Temperature Operation
Operating Temperature Range
SM Test Results
±1.0%
± 0.5%
±1.0%
±1.0%
±1.0
±0.5%
±0.001%/V
±0.5%
±0.5%
-55°C to +275°C
SMX Test Results
±1.5%
±1.0%
±5.0%
±1.0%
±1.0
±0.5%
±0.001%/V
±0.75%
±0.5%
-55°C to +155°C
Toll Free: (888) SEI-SEIS
(888) 734-7347
www.seielect.com
46
email: marketing@seielect.com
