General Note
IRC reserves the right to make changes in product specification without notice or liability.
All information is subject to IRC’s own data and is considered accurate at time of going to print. A subsidiary of
TT electronics plc
Advanced Film Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com LRF3W Series Issue July 2008
Low Range 3 Watt
SMT Chip Resistor
• Tolerances to ±1%
• 3 Watt @70°C power dissipation in a compact 1225 package
• Resistance range from 0.002 to 0.100Ω
• Ideal for high current sensing applications
• Standard Sn/Pb and Pb-free (matte tin) terminations available
Electrical Data
LRF3W Series
Environmental Data
Environmental Test Test Method Performance (Resistance Change)
Thermal Shock MIL-STD-202 Method 107
Condition F, -65°C to +150°C ±0.25% (+0.001Ω)
Short-time Overload 5 Seconds, 2 X Rated Power
Maximum 25 Amps ±0.5% (+0.0005Ω)
High Temperature Exposure MIL-PRF-55342
100 Hours, 150°C, No Power ±0.5% (+0.0005Ω)
Load Life 1000 Hours, 70°C, Rated Power ±1.0% (+0.0005Ω)
Moisture Resistance MIL-STD-202 Method 106
No Bias ±0.5% (+0.0005Ω)
Low Temperature Operation MIL-PRF-55342 ±0.25% (+0.0005Ω)
Resistance To Solder Heat MIL-STD-202 Method 210 ±0.25% (+0.001Ω)
Leach Resistance Molten Solder 250°C 90 seconds minimum
IRC’s LRF3W series combines high power capabilities with small chip
size and very low resistance to handle your current sensing needs.
The LRF3W utilizes IRC’s proprietary thick film materials which possess superior thermal conductivity over
other technologies. The result is significantly lower operating temperature and higher power dissipation.
Termination on the long sides minimizes TCE mismatch to PCBs.
Resistance
Range(Ω)
Absolute
TCR
(ppm/°C)
Available Absolute
Tolerances
Rated
Power @
70° (W)
Voltage
Rating
(V)
Operating
Temperature
Range
Termination
0.002 - 0.004 ±550 ±5%, ±10%
3.0* P x R -55°C to +150°C Sn/Pb solder or matte tin
plated over nickel
0.005 - 0.100 ±100 ±1%, ±2%, ±5%, ±10%
*Note: 3-Watt rating achieved with 500mm2 Copper pad area around each termination pad. Maximum current is 25 amps.
√
LRF3W Series Issue July 2008
Advanced Film Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
Low Range 3 Watt
SMT Chip Resistor
Temperature Rise Data
Pulse Power Data
LRF3W Series Issue July 2008
Advanced Film Division • 4222 South Staples Street • Corpus Christi Texas 78411 USA
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
Prefix LRC - LRF3WLF - 01 - R020 - F
Model
LRF3W = 3 watt chip with standard Sn/Pb termination
LRF3WLF = 3 watt chip with Pb-free (matte tin) termination
TCR Code
Resistance Code
4-Digit resistance code
Example: R050 = 0.050Ω; R005 = 0.005Ω
Tolerance Code
K = ±10%; J = ±5%; G = ±2%; F = ±1%
For additional information or to discuss your specific requirements,
please contact our Applications Team using the contact details below.
Power Derating Curve Ordering Data
Physical Data
Low Range 3 Watt
SMT Chip Resistor
