Precision Metal Film Resistors 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 COMMERCIAL Power rating at 70°C Resistance range Limiting element voltage Isolation voltage TCR (20 to +70°C) & codes Resistance tolerance RC70 NOTES 0.25 0.5 1.0 1R to 4M 1R to 4M 1R to 10M 350 350 500 500 500 700 5(V), 10(T), 15(Y), 25(D), 50(C) & 100(Z) 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) See resistance restrictions APPROVED CECC 40101-004 H J K K L Power rating at 70°C watts 0.063 0.125 0.25 0.25 0.5 Resistance range ohms 1R to 1M 1R to 1M 1R to 1M 10R to 1M 10R to 1M Limiting element voltage volts 200 200 250 250 350 Isolation voltage volts 280 280 350 350 500 TCR & codes ppm/°C 15(Y), 25(D), 50(C) & 100(Z) Resistance tolerance (code) % 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) See resistance restrictions APPROVED CECC 40101-804 Power rating at 70°C watts Resistance range ohms Limiting element voltage volts Isolation voltage volts TCR & codes ppm/°C Resistance tolerance (code) % See resistance restrictions Standard values Thermal impedance Ambient temperature range watts ohms volts volts ppm/°C % RC65 °C/watt °C A 0.125 1R to 1M 200 280 B 0.25 1R to 1M 250 350 B C 0.25 0.5 10R to 1M 10R to 1M 250 350 350 500 15(T), 25(E) & 50(C) 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) 110 E24, E96 preferred 70 -55 to +155 60 Any value to order 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. © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, England Tel: 01670 822181 Fax: 01670 829465 Web: http://www.Welwyn-TT.co.uk Issue A 07/99 173 Precision Metal Film Resistors RC SERIES Physical Data Dimensions (mm) & Weight (g) Type RC55 RC65 RC70 L max 7.2 10.0 15.5 D max 2.5 3.7 5.5 f min 30 30 30 d nom 0.6 0.6 0.8 PCB mounting centres 10.2 12.7 18.4 CONSTRUCTION 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. The resistor is adjusted to value by a helical cut in the film and the body is protected with a specially formulated epoxy coating. TERMINATIONS Material Solder coated copper wire Strength The terminations meet the requirements of IEC 68.2.21. Solderability The terminations meet the requirements of IEC 115-1, Clause 4.17.3.2. Min. Bend Radius 0.6 0.6 1.2 Wt. nom 0.24 0.40 1.15 d D L f MARKING Type reference, TCR code, resistance value and tolerance code. The resistance values conform to IEC 62. SOLVENT RESISTANCE The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits. Performance Data Load at commercial rating: 1000 hours at 70°C ∆R% Load at CECC rating: 1000 hours at 70°C ∆R% Dry heat: 1000 hours at 155°C ∆R% Shelf life: 12 months at room temperature ∆R% Derating from rated power at 70°C Short term overload ∆R% Climatic ∆R% Climatic category Long term damp heat ∆R% Temperature rapid change ∆R% Resistance to solder heat ∆R% Vibration and bump ∆R% Noise (in a decade of frequency) µV/V Voltage coefficient of resistance ppm/V CECC 40101-004 CECC 40101-804 *ACTUAL PERFORMANCE REQUIREMENTS REQUIREMENTS MAXIMUM TYPICAL 0.3 0.1 0.5 0.5 0.3 0.05 0.5 0.5 **1.0 0.15 Not specified Not specified 0.1 0.03 Zero at 155°C 50% at 125°C 0.1 0.1 0.1 0.02 0.5 0.5 0.3 0.1 55/155/56 55/125/56 55/155/56 0.5 0.5 0.5 0.1 0.1 0.1 **0.2 0.05 0.1 0.1 0.06 0.03 0.1 0.1 0.06 0.02 Not specified Not specified 1.0 0.1 Not specified Not specified <1 Note: *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. © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, England Tel: 01670 822181 Fax: 01670 829465 Web: http://www.Welwyn-TT.co.uk 174 Issue A 07/99 Precision Metal Film Resistors RC SERIES Table of Resistance Restrictions TCR ppm/°C 5 10 15 25 50 100 RC55 0.05% .1 – .25% 10 to 500k 10 to 500k 10 to 1M 10 to 1M 10 to 1M 5 to 1M 10 to 1M 5 to 2M 10 to 1M 5 to 2M 10 to 1M 1 to 2M TOLERANCE RC65 .5 – 1% 0.05% .1 – .25% 1 to 500k 10 to 500k 10 to 500k 1 to 1M 10 to 1M 10 to 1M 1 to 1M 10 to 1M 5 to 1M 1 to 2M 10 to 1M 5 to 2M 1 to 4M 10 to 1M 5 to 2M 1 to 4M 10 to 1M 1 to 2M 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. The individual resistors within a set or module can be manufactured with a tolerance of ±0.05% and TCR of ±5ppm/°C. RC70 0.05% .1 – .25% 10 to 750k 10 to 750k 10 to 1M 10 to 1M 10 to 1M 10 to 2M 10 to 1M 10 to 5M 10 to 1M 5 to 10M 10 to 1M 1 to 10M .5 – 1% 1 to 500k 1 to 1M 1 to 1M 1 to 2M 1 to 4M 1 to 4M .5 – 1% 1 to 750k 1 to 1M 1 to 2M 1 to 5M 1 to 10M 1 to 10M 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. 5 f1 6 f2 52 6 Body location f1 – f2 ≤ 1.4 mm STANDARD QUANTITIES PER PACKAGE Type Small Box Large Box Reel Large Ammo Pack RC55 250 1000 5000 1000 RC65 125 500 2500 1000 RC70 25 250 - © Welwyn Components Limited Bedlington, Northumberland NE22 7AA, England Tel: 01670 822181 Fax: 01670 829465 Web: http://www.Welwyn-TT.co.uk Issue A 07/99 175