Precision Metal Film Resistors Welwyn Components RC series * CECC released products with low TCRs over a wide resistance range * Resistance tolerance down to 0.05% * Express delivery available * Low noise and negligible voltage coefficient Electrical Data RC55 RC65 RC70 Notes Commercial Power rating at 70C watts 0.25 0.5 1.0 Resistance range 1R to 10M ohms 1R to 4M 1R to 4M Limiting element voltage volts 350 350 500 Isolation voltage volts 500 500 700 TCR (20 to +70C) & codes Resistance tolerance ppm/C 5(V), 10(T), 15(Y), 25(D), 50(C) & 100(Z) See resistance 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions % Approved CECC 40101-004 H J K K L 0.063 0.125 0.25 0.25 0.5 10R to 1M 10R to 1M Power rating at 70C watts Resistance range ohms 1R to 1M 1R to 1M 1R to 1M Limiting element voltage volts 200 200 250 250 350 Isolation voltage volts 280 280 350 350 500 TCR & codes Resistance tolerance (code) ppm/C % Approved CECC 40101-804 15(Y), 25(D), 50(C) & 100(Z) See resistance 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions A B B C Power rating at 70C watts 0.125 0.25 0.25 0.5 Resistance range ohms 1R to 1M 1R to 1M 10R to 1M 10R to 1M Limiting element voltage volts 200 250 250 350 Isolation voltage volts 280 350 350 500 TCR & codes Resistance tolerance (code) ppm/C % 15(T), 25(E) & 50(C) See resistance 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions Standard values Thermal impedance Ambient temperature range E24, E96 preferred C/watt 110 C 70 Any value 60 to order -55 to +155 General Note Welwyn Components reserves the right to make changes in product specification without notice or liability. All information is subject to Welwyn's own data and is considered accurate at time of going to print. A subsidiary of TT electronics plc (c) 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 B * 03.02 173 Precision Metal Film Resistors Welwyn Components RC series Physical Data Dimensions (mm) & Weight (g) PCB Min. mounting Bend Type L max D max f min d nom centres Radius Wt. nom RC55 7.2 2.5 30 0.6 10.2 0.6 0.24 RC65 10.0 3.7 30 0.6 12.7 0.6 0.40 RC70 15.5 5.5 30 0.8 18.4 1.2 1.15 d D L Construction Marking A metal film is deposited onto a high quality ceramic former. Nickel-plated steel caps are force fitted to the former and termination wires are welded to the caps. Type reference, TCR code, resistance value and tolerance code. f The resistance values conform to IEC 62. The resistor is adjusted to value by a helical cut in the film and the body is protected with a specially formulated epoxy coating. Solvent Resistance The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Terminations Material Strength Solderability Solder coated copper wire The terminations meet the requirements of IEC 68.2.21. The terminations meet the requirements of IEC 115-1, Clause 4.17.3.2. Performance Data CECC 40101-004 CECC 40101-804 Requirements Maximum Typical Load at commercial rating: 1000 hours at 70C R% 0.3 0.1 Load at CECC rating: 1000 hours at 70C R% 0.5 0.5 0.3 0.05 Dry heat: 1000 hours at 155C R% 0.5 0.5 **1.0 0.15 Shelf life: 12 months at room temperature R% 0.1 0.03 0.1 0.02 0.1 Derating from rated power at 70C Short term overload R% Climatic R% Climatic category Not specified Not specified Zero at 155C 50% at 125C 0.1 0.1 0.5 0.5 0.3 55/155/56 55/125/56 55/155/56 Long term damp heat R% 0.5 0.5 0.5 0.1 Temperature rapid change R% 0.1 0.1 **0.2 0.05 Resistance to solder heat R% 0.1 0.1 0.06 0.03 Vibration and bump R% 0.1 0.1 0.06 0.02 Noise (in a decade of frequency) V/V Not specified Not specified 1.0 0.1 Voltage coefficient of resistance ppm/V Not specified Not specified Note: <1 *An 0.01 ohm addition to be added to the performance claims of all resistors <10R. ** All products within the specified approved range meet CECC requirements. (c) 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 174 *Actual Performance Requirements Issue B * 03.02 Precision Metal Film Resistors Welwyn Components RC series Table of Resistance Restrictions Tolerance TCR ppm/C RC55 RC65 RC70 0.05% .1 - .25% .5 - 1% 0.05% .1 - .25% .5 - 1% 0.05% .1 - .25% .5 - 1% 5 10 to 500k 10 to 500k 1 to 500k 10 to 500k 10 to 500k 1 to 500k 10 to 750k 10 to 750k 1 to 750k 10 10 to 1M 10 to 1M 1 to 1M 10 to 1M 10 to 1M 1 to 1M 10 to 1M 10 to 1M 1 to 1M 15 10 to 1M 5 to 1M 1 to 1M 10 to 1M 5 to 1M 1 to 1M 10 to 1M 10 to 2M 1 to 2M 25 10 to 1M 5 to 2M 1 to 2M 10 to 1M 5 to 2M 1 to 2M 10 to 1M 10 to 5M 1 to 5M 50 10 to 1M 5 to 2M 1 to 4M 10 to 1M 5 to 2M 1 to 4M 10 to 1M 5 to 10M 1 to 10M 100 10 to 1M 1 to 2M 1 to 4M 10 to 1M 1 to 2M 1 to 4M 10 to 1M 1 to 10M 1 to 10M Application Notes Matched Sets and Networks Welwyn has many years experience in the supply of matched set of precision resistors. Resistors can be supplied matched for tolerance and TCR down to 0.02% and 2ppm/C, either as separate resistors or pre-assembled and encapsulated within a plastic box. Packaging The standard method of packaging RC55 resistors is taped in ammo packs. Taped resistors on reel or loose packed components can also be supplied by special request. The standard packaging for RC65 and RC70 resistors is loose in boxes. By special request the RC65 components can also be supplied taped on reel or in ammo pack. In the case of tape packed components the usable lead length is reduced by the width of the tape. The individual resistors within a set or module can be manufactured with a tolerance of 0.05% and TCR of 5ppm/C. 5 A low inductance version is available at 1% tolerance. For low inductance version add suffix N. f1 f2 52 6 6 Body location f1 - f2 1.4 mm Standard Quantities Per Package Type RC55 RC65 RC70 Small box 250 125 25 Large box 1000 500 250 Reel 5000 2500 - Large ammo pack 1000 1000 - (c) 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 B * 03.02 175