SMF 2W to 5W Series Power Metal Film Chip Resistors
Power metal film chip resistor in UL94V-0 flameproof moulded package
Three power ratings: 2W, 3W and 5W
Resistance range 10Ω to 2MΩ
Tolerance options ±1% (F) and ±5% (J)
TCR ±100ppm/°C maximum
Maximum working voltage 300V (2W) and 500V (3W and 5W)
Short-time overload rating of 5× rated power for 5 seconds
Operating temperature range −55°C to +200°C
Insulation resistance 10,000MΩ minimum at DC 500V
Designed for seamless automatic surface mounting
Tape-and-reel packaging for automated pick-and-place assembly
Consumer electronics, computers, telecommunications and control instrument applications
What are the SMF 2W to 5W Series Power Metal Film Chip Resistors?
The SMF series are power metal film chip resistors housed in a UL94V-0 rated flameproof moulded package, designed for high-power surface-mount applications where stability, reliability and resistance to environmental stress are essential. The metal film resistive element delivers tighter performance than wirewound or carbon film alternatives at equivalent power ratings, with a TCR of ±100ppm/°C maximum and load life stability of ±1.0% after 1000 hours — half the drift permitted by the companion SMW wirewound series. Three body sizes cover continuous power ratings of 2W, 3W and 5W at an ambient temperature of 20°C, with derating applied above that point up to the maximum operating temperature of +200°C.
The SMF 2W measures 6.7mm × 4.0mm and covers a resistance range of 10Ω to 2MΩ with a maximum working voltage of 300V. The SMF 3W (10.5mm × 5.5mm) and SMF 5W (13.5mm × 7.3mm) extend the same 10Ω to 2MΩ resistance range with a higher maximum working voltage of 500V, reflecting the larger body dimensions and greater creepage distance of these models. All three variants are available in ±1% (F) and ±5% (J) tolerances. Non-standard ohmic values are available on request. The maximum working voltage across the SMF range is governed by E = √(P×R) where this formula yields a lower value than the stated voltage ceiling.
Short-time overload performance is ±0.5% resistance change at 5 times rated power for 5 seconds, and moisture load life stability is ±1.0% after 500 hours at 40°C and 90–95% RH with rated power applied. Dielectric withstanding voltage is AC 500V for 1 minute, and insulation resistance is guaranteed at 10,000MΩ minimum under DC 500V. The moulded package provides inherent resistance to heat and humidity while delivering excellent insulation properties, and the body construction is specifically engineered for automatic surface mounting with outstanding mechanical strength and electrical stability.
The SMF series is supplied in tape-and-reel format for pick-and-place assembly. The 2W size (1WL carrier tape) ships at 2000 pieces per reel on 16mm tape, the 3W size (2WL) at 1000 pieces per reel on 24mm tape, and the 5W size (3WL) at 500 pieces per reel on 32mm tape. The standardised tape dimensions ensure compatibility with standard SMD assembly equipment across all three body sizes. Reduced assembly costs are a direct benefit of the surface-mount format and the package’s special design for seamless automated placement.
SMF 2W to 5W Series Power Metal Film Chip Resistors Specifications
A practical overview for engineers and procurement teams evaluating resistive solutions.
Model: SMF
Resistor type: Power film
Description: Chip
Power Rating: 2W, 3W, 5W
Resistance (Ω): 10~20M
Tolerance (%): ±1, ±5
TCR (ppm/C): 100
Applications of the SMF 2W to 5W Series Power Metal Film Chip Resistors
Where RARA metal clad resistors are deployed in the field.
-Consumer electronics — compact high-power SMD resistors in space-constrained PCB designs
-Computers and server power supplies — stable metal film resistors in voltage regulation and feedback circuits
-Telecommunications equipment — reliable SMD power resistors in line cards and power management assemblies
-Industrial control instruments — precision metal film chip resistors in measurement and sensing circuits
-Power supply design — output filter, divider and feedback network resistors requiring low drift
-DC-DC converters and voltage regulators — high-stability SMD resistors in switching power stages
-Motor drive and inverter control boards — surface-mount power resistors in gate drive and protection circuits
-Automotive electronics — high-temperature-rated SMD resistors in ECU and power module assemblies
-Test and measurement equipment — precision load and attenuator resistors in automated test systems
-High-density PCB assemblies — tape-and-reel power resistors optimised for automated pick-and-place production
Related Products of the SMF 2W to 5W Series Power Metal Film Chip Resistors
Model: CFS
Resistor type: Power film
Description: Carbon film, MELF
Power Rating: 1/4W~2W
Resistance (Ω): 1~1M
Tolerance (%): ±2, ±5
TCR (ppm/C): 350~1000
Model: TNP25, TNP45
Resistor type: Power film
Description: SMD surge protection
Power Rating: 25W, 45W
Resistance (Ω): 0.1~51k
Tolerance (%): ±1
TCR (ppm/C): 100
Model: ARN
Resistor type: Aluminum nitride
Description: Chip
Power Rating: 1/2W, 1W, 2W, 6W
Resistance (Ω): 50~30.1k
Tolerance (%): ±0.1
TCR (ppm/C): 25, 50
Model: CRP
Resistor type: Aluminum nitride
Description: Chip
Power Rating: 2.4W, 3.5W
Resistance (Ω): 10~2k
Tolerance (%): ±1, ±5
TCR (ppm/C): 150
Why Choose RARA Metal Clad Resistors
What sets RARA apart for engineers and procurement managers in industrial and automotive markets.
01
Automotive Qualified
AEC-Q200 tested models and IATF 16949 certification for EV and automotive powertrain applications. Trusted by GM Korea, Tesla, and Proterra.
02
STEP Files Included
3D STEP files available for core models, supporting ECAD/MCAD integration and thermal management simulation in your design workflow.
03
Wide Power Range
A single product family spanning 10W to 8.5kW means you can source across a project from one qualified, certified supplier.
04
Global Track Record
Deployed by Siemens, Rockwell, Toshiba, Schneider Electric, LG, and Hanwha — a customer list built on decades of consistent performance.
