3812

Ultra-High Value Precision Resistors 3810 Series Welwyn Components • Resistance range up to 100 T ohms (1014 ohms) • Designed for low current (pica ampere level) measurements • • • Low voltage coefficient Hermetically sealed Leakage current minimised by hermetic sealing and guard ring Electrical Data 3810 Resistance range Limiting element voltage TCR (20°C to 70°C) Resistance tolerance Values Ambient temperature range °C ohms volts ppm/°C % 10, 20 100M to 1T 500 3811 100M to 1T 1000 -500 to -3500 1, 2, 5, 10 E24 preferred -40 to 100 1T to 10T; 2, 5, 10 >10T; 5, 10 3812 1T to 100T 1000 Physical Data Dimensions (mm) & Weight (g) Type 3810 3811 3812 L max 25.0 42.9 48.0 D max 6 6 6 f min 30 30 30 d nom 0.6 0.6 0.6 PCB mounting Centres 29.2 47.1 52.2 Min. Bend Radius 0.6 0.6 0.6 Wt. nom d 1.5 2.2 2.5 D L f Construction The Cermetox® resistive film is fired onto high quality ceramic substrate; brass end caps are forced fitted to the substrate which is then adjusted to value with a helical cut in the film; the leads are mechanically locked into the end caps and the assembly sealed into the glass envelope. All close tolerance units utilise two resistors connected in series within the glass envelope. The guard band is described, with application notes, in a Product Information sheet, available on request. Marking The serial number, resistance value and tolerance code are legend marked. The resistance value marking conforms to IEC 62. Solvent Resistance The glass envelope is coated with silicone and should not be subjected to solvents or their vapours. (See Application Notes.) Terminations Material Strength Solder-coated Dumet wire. 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 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 Issue D · 03.06 © 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 203 Ultra-High Value Precision Resistors 3810 Series Welwyn Components Performance Data Maximum Load at rated voltage: 1000 hours at 20°C Shelf life: 12 months at room temperature Resistance to solder heat Capacitance 3810 3811 ∆R% ∆R% ∆R% pF pF 2 1 0.2 0.4 0.2 Typical 1 0.5