Molded Surface Mount Wirewound Resistor Molded Surface Mount *Wirewound Flexible Terminations Resistor * All welded construction WSM Series * Ideal for automatic pick and place * Lead free, RoHS compliant construction only * Contact WSM Seriesfactory for ohmic values above * * * * * published ranges Flexible Terminations All welded construction Ideal for automatic pick and place Lead free, RoHS compliant construction only Contact factory for ohmic values above published ranges Electrical Data IRC Type Power Rating Resistance Maximum Working @ 70C Range Voltage (watts) (ohms) (volts) WSM-1 1W 0.01 to 1K WSM-2 2W 0.01 to 2K WSM-3 3W 0.01 to 3K P x R Resistance Standard Tolerance Values (%) TCR (ppm/C) 0.1:- <10:: 100 t1:: 20 *1, 2, 5, 10 E24 Preferred Ambient Temperature (C) -55 to 155 *Note: 5% or 10% preferred below 0.1 ohms. CONSTRUCTION A high purity ceramic substrate is assembled with interference fit end caps to which are welded the terminations. The resistive element is wound on the substrate and welded to the caps. The unit is then molded. FLAMMABILITY The resistor coating is categorized as flame retardant epoxy under UL-94. SOLVENT RESISTANCE The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. MARKING WSM resistors are legend marked with type, value and tolerance. GeneralNote Note General IRC reserves the right to makethe changes product specifi cation without notice orspecification liability. TT electronics reserves rightinto make changes in product without notice or liability. All information is subject to IRC's own data and is considered accurate at time of going to print. All information is subject to TT electronics' own data and is considered accurate at time of going to print. Wire and Film Technologies Division * 4222 South Staples Street * Corpus Christi Texas 78411 USA Telephone: 361 992 7900 * Facsimile: (c) TT electronics plc 361 992 3377 * Website: www.irctt.com A subsidiary of www.bitechnologies.com www.irctt.com www.welwyn-tt.com TT electronics plc WSM Series Issue August 2009 Sheet 1 of 3 12.12 Molded Surface Mount Wirewound Resistor Molded Surface Mount Wirewound Resistor WSM Series Recommended Pad Sizes B C A D Dimensions (Inches & mm)) Type A B C D WSM-1 0.13 inch (3.3 mm) 0.138 inch (3.5 mm) 0.074 inch (1.9 mm) 0.35 inches (8.9 mm) WSM-2 0.157 inch (4.0 mm) 0.181 inch (4.6 mm) 0.221 inch (5.6 mm) 0.583 inch (14.8 mm) WSM-3 0.85 inch (21.6 mm) 0.236 inch (6.2 mm) 0.378 inch (9.6 mm) 0.85 inch (21.6 mm) Physical Data L l A W H Dimensions Inches (mm) Type L l A W H WSM-1 0.310 max (7.9 max) 0.115 max (2.9 max) 0.275 max (7.0 max) 0.165 max (4.2 max) 0.155 max (3.94 max) WSM-2 0.473 max (12 max) 0.137 max (3.5 max) 0.425 max (10.8 max) 0.260 max (6.6 max) 0.195 max (5.0 max) WSM-3 0.677 max (17.2 max) 0.137 max (3.5 max) 0.64 max (16.3 max) 0.29 max (7.4 max) 0.265 inch (6.7 max) Wire and Film Technologies Division s 3OUTH 3TAPLES 3TREET s #ORPUS #HRISTI TEXAS 53! TELEPHONE: s FACSIMILE: s WEBSITE: WWWIRCTTCOM 73- 3ERIES )SSUE !UGUST 3HEET OF General Note TT electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT electronics' own data and is considered accurate at time of going to print. www.bitechnologies.com www.irctt.com www.welwyn-tt.com (c) TT electronics plc 12.12 Molded Surface Mount Wirewound Resistor Molded Surface Mount Wirewound Resistor WSM Series Environmental Data Characteristics WSM-1 WSM-2 WSM-1 Load at Rated Power: 1000 hours @ 70C 'R% 2 0.001: 2 0.001: 3 0.001: Dry Heat: 'R% 2 0.001: 2 0.001: 3 0.001: 1000 hours @ 155C 'R% Short Term Overload 2 0.001: Derating from Rated Power @ 70C zero at 155C Moisture 'R% Temperature Cycling 'R% 1 0.001: Resistance to Solder Heat 'R% 1 0.001: Isolation Voltage volts 1,000 Insulation Resistance ohms >1000M Substrate Bend 'R% 0.2 0.001: 1 0.001: 1 0.001: 1.5 0.001: *Note: The power ratings to be applied depend upon the board used and the ambient temperature. Standard Quantities Per Package Ordering Data Specify type, reference, etc. as indicated in this example of a WSM3 6801 F resistor with tape and reel packaging. Sample Part No. WSM3 6801 F LF TR IRC Type Type Code WSM1 WSM2 WSM3 13" Reel (330mm) R 1500 800 750 Packaging: (WSM1, WSM2, WSM3) Resistance Value WSM2 resistors are supplied on .945 (24mm) wide carrier tape. (100: and greater - First 3 significant digits plus 4th digit multiplier) Example: 100: = 1000, 1000: = 1001, 150,000: = 1503 (Less than 100: - "R" is used to designate decimal) Example: 51: = 51R0, 1: = 1R00, 0.25: = R250 WSM3 resistors are supplied on 1.26 (32mm) wide carrier tape. Tolerance (K = 10%, J = 5%, G = 2%, F = 1%) Both products are reeled onto 13.00 (330mm) diameter reels. Lead Free, RoHS Designator Packaging Code (TR = 13" Reel) *For packaging information, see Appendix "A". Dimensions (Inches and (mm)) Ao Bo Ko W P T WSM1 .165 (4.2) .300 (7.62) .165 (4.20) .630 (16.0) .315 (8.00) .014 (0.36) WSM2 .266 (6.75) .470 (11.95) .206 (5.22) .945 (24.0) .473 (12.0) .014 (0.36) WSM3 .288 (7.3) .721 (18.3) .264 (6.7) 1.26 (32.0) .473 (12.0) .016 (0.4) A0 B0 Wire and Film Technologies Division * 4222 South Staples Street * Corpus Christi Texas 78411 USA Telephone: 361 992 7900 * Facsimile: 361 992 3377 * Website: www.irctt.com K0 P W t WSM Series Issue August 2009 Sheet 3 of 3 General Note TT electronics reserves the right to make changes in product specification without notice or liability. All information is subject to TT electronics' own data and is considered accurate at time of going to print. www.bitechnologies.com www.irctt.com www.welwyn-tt.com (c) TT electronics plc 12.12