Ultra Precision Bulk Metal Film Resistors Welwyn Components 4800 Series * * * * * * Tolerances down to 0.005% Current noise and distortion below level of practible measurement Low thermal e.m.f Ideal resistor for precision instrumentation Use of bulk metal gives superior stability Planar construction gives low residual capacitance and inductance Electrical Data Commercial 48 02/12/32 4804 4805 4802/12 0.5 1 1.5 0.25 Power Rating at 70C watts Resistance Range ohms 1R0 to 100K 0R5 to 200K R33 to 300K Limiting element voltage TCR (20 to 70C) volts 100 to 56K 200 350 500 200 ppm/C 5 5 5 5 C/watt 250 130 Resistance tolerance Thermal impedance See table 1 below Values Ambient temperature range Notes 80 E24 and E96 preferred C Any value to order -55 to 155 All styles and products Table 1. Resistance Range (ohms) and Tolerance (%) 4802/12/32 4804 4805 0.005 (E) Tolerance (code) 200R to 100K 100R to 200K 65R to 300K 0.01 (L) 100R to 100K 50R to 200K 33R to 300K 0.02 (P) 50R to 100K 25R to 200K 17R to 300K 0.05 (W) 25R to 100K 10R to 200K 8R to 300K 0.1 (B) 10R to 100K 5R to 200K 3.3R to 300K 0.25 (C) 5R to 100K 2R to 200K 1.7R to 300K 0.5 (D) 2R to 100K 10R to 200K 0.6R to 300K 1.0 (F) 1R to 100K 0.5R to 200K 0.33R to 300K 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. (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 A subsidiary of TT electronics plc 07.11 Ultra Precision Bulk Metal Film Resistors Welwyn Components 4800 series Physical Data Dimensions (mm) & Weight (g) Type L max H max W max T min d nom S nom Wt. nom 4802 8.9 10.2 3.8 30 0.6 5.1 1 4812 7.5 8 2.5 30 0.6 5.1 0.6 4804 15.2 13.2 3.8 30 0.6 10.2 1.5 4805 22.6 13.2 3.8 30 0.6 17.8 2 4832 9.7 5.4 9.7 30 0.6 1.5 1.1 4802/12/04/05 L W H d dia T S 4832 d Construction Terminations The resistor element is an etched bulk metal foil, bonded to an alumina substrate. Connections to the foil are made by copper wires welded to the foil to minimise thermal e.m.f. Before encapsulation, the resistor element is coated with silicone rubber to isolate the element from mechanical stress which would adversely affect the carefully balanced construction and result in poor resistance/temperature characteristics. Material Strength H L W T S 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. Solderability Marking Type reference, resistance value, tolerance and date code are legend marked. The resistance value conforms to IEC 62. Solvent Resistance The protection will withstand all normal industrial solvents suitable for cleaning printed circuit boards. Performance Data Actual Load at commercial rating: 1000 hours at 70C Dry heat: 1000 hours at 155C Shelf life: 12 months at room temperature Derating from rated power at 70C Short term overload Climatic category Climatic Long term damp heat Temperature rapid change Resistance to solder heat Vibration and bump Noise. (in a decade of frequency) Voltage coefficient of resistance Insulation Resistance Inductance Capacitance R% R% R% Maximum 0.05 0.05 Typical 0.02 0.02 0.0025 Zero at 155C R% 0.01 0.005 55/155/56 R% R% R% R% R% V/V ppm/V ohms H pF 0.05 0.05 0.01 0.01 0.01 0.03 0.03 0.005 0.005 0.005 Below level of practicable measurement >1000M 0.2 1 0.08 0.5 Packaging All components are supplied loose packed in either plastic bags or panel boxes. Quantity per box will depend on resistor size. (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 07.11 187 Ultra Precision Bulk Metal Film Resistors Welwyn Components 4800 series Ordering Procedure Example: 4812 at 73.2 kilohms and 0.01% tolerance 4812- 73K2LI Type Value (use IEC62 code) Tolerance (use IEC62 code) E L P W 0.005% 0.01% 0.02% 0.05% Packing I B C D F Bag / Box 0.1% 0.25% 0.5% 1% Standard (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 07.11