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Resistor Wirewound Precision SMT

This specific product line is not for new designs. Johanson’s Surface Mount Precision Wirewound Resistor (RWF Series) features ultra-tight tolerance to ± 0.01% and exhibits a temperature coefficient of as low as ± 20ppm/°C. This series offers options for low inductance windings, has good pulse handling capability and UL94-V0 flameproof protection. The small-profile design of this resistor helps satisfy the growing demand for new high density boards fabricated with automated pick and place equipment. Resistance value goes as low as 0.005 ohms, and non-inductive windings are available.
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Mechanical Characteristics

Lead Thickness 0.006 [.015mm] Tolerances ±0.002” [±0.05mm]
Package Code C1 C2 C3 C4 C5 D1 D2
Dimensions
Inches [mm]
 A (Tolerances)
±0.015” [±0.4mm]
0.190 [4.83]
0.260 [6.60]
0.450 [11.43]
0.625 [15.83]
0.820 [20.83]
0.260 [6.60]
0.450 [11.43]
B (Tolerances)
±0.015” [±0.4mm]
0.130[ 3.30]
0.155 [3.94]
0.250 [6.35]
0.270 [6.86]
0.295 [7.49]
0.155 [3.94]
0.250 [6.35]
C (Tolerances)
±0.015” [±0.4mm]
0.110 [2.79]
0.125 [3.18]
0.180 [4.57]
0.250 [6.35]
0.305 [7.75]
0.100 [2.54]
0.100 [2.54]
D (Tolerances)
±0.015” [±0.4mm]		 .060 [1.52]
0.070[1.78]
0.120 [3.05]
0.120 [3.05]
0.150 [3.81]
0.070 [1.79]
0.120 [3.05]
E (Tolerances)
±0.015” [±0.4mm]]
0.040 [1.02]
0.070 [1.78]
0.100 [2.54]
0.135 [3.43]
0.190 [4.83]
0.070 [1.79]
0.100 [2.54]
Stand-Off
Inches [mm]
 E (Tolerances)
±0.015” [±0.4mm]
0.100 [2.54]
0.120 [3.05]
0.190 [4.83]
0.150 [3.81]
0.245 [6.22]
0.120 [3.05]
0.190 [4.83]
Height (Tolerances)
±0.005”[±0.13mm]
0.005 [0.13]
0.005 [0.13]
0.005 [0.13]
0.005 [0.13]
0.005 [0.13]
0.005 [0.13]
0.005 [0.13]
Solder Pad
Inches [mm]
 Width (Tolerances)
±0.015” [±0.4mm]
0.062 [1.57]
0.096 [2.44]
0.150 [3.81]
0.200 [5.08]
0.220 [5.59]
0.096 [2.44]
0.150 [3.81]
Height (Tolerances)
±0.015” [±0.4mm]
0.100 [2.54]
0.150 [3.81]
0.200 [5.08]
0.220 [5.59]
0.250 [6.35]
0.150 [3.81]
0.200 [5.08]
Length (Tolerances)
±0.015” [±0.4mm]
0.250 [6.35]
0.070 [1.78]
0.540 [13.72]
0.700 [17.78]
0.337 [8.56]
0.337 [8.56]
0.540 [13.72]

Environmental Performance

Environmental Performance (MIL-STD 202)
tringle symbolR Maximum
Load Life
±1% + 0.05 Ω
Moisture Resistance
Dielectric
±0.5% + 0.05 Ω
Storage
Shock
±0.5% + 0.05 Ω
Thermal Shock
5X Overload (5s)
Resistance to Heat Solder (260C, 10s)

Packaging Information

Package Code C1 C2 C3 C4 C5 D1 D2
Reel/Tape Width [mm] 12 16 24 24 32 16 24
Small 650 600 250 125 180 600 250
Large 3000 2000 1000 500 500 2000 1000
Humidity Packaging Notes:
Moisture Barrier Bags (MBB) are used to package surface mount components. These bags include a dessicant and a Humidity Indicator Card to monitor humidity levels. All bags are marked with Moisture-Sensitive Identification Labels. A Moisture Sensitivity Level (MSL) rating of 2 (1-year floor life) applies to the Johanson RWF Series.

Available Options

  • Special Testing Requirements
  • Special Pulse Requirements

KEY FEATURES:

  • Resistance from 0.005 to 50kOhms
  • Precision, Flame Proof and Pulse Withstanding
  • Tolerance to ± 0.01%
  • High Power to 4 Watts
  • Flame Resistant UL 94V-0


  • Superior Surge Handling Capability
  • High Temperature Rating up to 275°C
  • Low Temperature Coefficient to ± 20ppm/°C
  • Non-Inductive Windings available
  • RoHS Compliant

APPLICATIONS:

  • Motor Control
  • Braking Systems
  • Power Supplies
  • Pressure Transducers
PRODUCT SERIES (RWF) RESISTANCE RANGE (Ω) 1 POWER RATING (W) @ 70 °C DIELECTRIC STRENGTH TOLERANCE TEMPERATURE COEFFICIENT TEMPERATURE RANGE INSULATION RESISTANCE
C1 0.01 to 400 0.5
1000 VAC
± 0.01% to
± 5%
  • >10 Ω : ± 20ppm/°C
  • 1 Ω to 10 Ω : ± 50ppm°C
  • <1 Ω : Call Factory
- 55°C to + 275°C
>1000 MOhms / Dry
C2 0.005 to 3k 1
C3 0.01 to 15k 2
C4 0.01 to 25k 3
C5 0.01 to 50k 4
D1 0.005 to 0.01 1
500 VAC
 ± ±1% to
±5%		 ± 200ppm/°C D2 0.005 to 0.07 2 Call Factory For Lower
D2 0.005 to 0.07 2

1 For non-inductive windings, divide max resistance by 2