Low Value 3W Welwyn Components Chip Resistors LRF3W Series 3 Watts 70C Resistance range from 0.003 to 0.1 Tolerances to 1% Electrical Data Power Derating Curve Characteristic Value 100 Power dissipation 70C 3 Watts 80 Resistance Range 0.005 to 0.100 60 Dielectric withstand 200V 40 Ambient temp range -55 to +150C R005 5%, >R005 2, 5%, 20 Resistance tolerance R01 1, 2, 5% 0 25 70 150 TCR 100ppm/C Temperature in C Pad & trace area for maximum 2 300mm power rating* Physical Data Top Bottom Recommended (Board Side) Solder Pad Layout 0.81 0.13mm 0.51 0.13mm 7.6mm 2.29 Plating 0.13mm wrap-around 6.35 0.13mm 2mm 1mm 0.94 mm max thickness 3.18 0.13mm Weight 0.065g typ. General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. A subsidiary of All information is subject to Welwyns own data and is considered accurate at time of going to print. TT electronics plc Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info welwyn-tt.com Website: www.welwyn-tt.com Issue D 07.06 84 % Of Power RatingLow Value 3W Chip Resistors Welwyn Components LRF3W Series Chips can withstand immersion in solder at 250C for Construction 90 seconds and are suitable for reflow or wave soldering Patented non-noble copper based thick film material, mounting applications. overglaze and organic protection are screen printed on a 96% alumina substrate. The components are laser trimmed to Marking achieve the required resistance tolerance. The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Terminations Chips are packed and mounted with marking side up. The wrap-around terminations have an electroplated nickel The LRF3W Chips are mounted with the actual resistor barrier and matte tin finish, this ensures excellent leach element mounted face down on its termination pads. resistance properties and solderability. Performance Data Typical Load at rated power: 1000 hours at 70C MIL-PRF-55342 R% 1 Overload: 6.25 x rated power for 2 seconds MIL-PRF-55342 R% 0.5 High temperature exposure: MIL-PRF-55342 R% 0.5 Low temperature operation: MIL-PRF-55342 R% 0.5 Low temperature storage: -65C, 100 hours R% 0.5 Moisture: MIL-PRF-55342 R% 0.5 Temperature cycling: MIL-STD-883 Method 1010 Test condition B R% 0.25 Thermal shock: MIL-STD-202 Method 107 condition B -65C +125C R% 0.25 Resistance to solder heat: MIL-STD-202 Method 210 R% 0.25 Shelf life test: 12 months at room temperature R% 0.1 Leach resistance: molten solder 250C 90 Seconds min. Packaging LRF3W Resistors are supplied taped and reeled as per IEC 286-3. The standard quantity per reel is 1800 parts. T 2 P 0 D 0 P 2 T 33 1.0 13 0.5mm Marking (Both sides) 13 0.5 T 1 A D 0 1 0.8 0.15 2.5 0.5 K 0 P 1 Tape dimensions in mm W P1 P0 P2 D0 D1 E F A0 B0 K0 T T1 T2 0.3 0.1 0.1 0.05 0.1 0.2 0.1 0.05 0.1 0.1 0.1 0.05 nom 0.15 LRF3W 12 8 4 2 1.5 1.5 1.75 5.5 3.61 6.96 1.17 0.28 0.06 1.45 Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK Telephone: +44 (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info welwyn-tt.com Website: www.welwyn-tt.com Issue D 07.06 85 178 2 80 2 B 0 GF E W