1268 Vishay Foil Resistors Bulk Metal® Foil Technology Precision Trimming Potentiometers 3/8 Inch Square, RJ24 Style - Industrial Trimmer FEATURES • Temperature Coefficient of Resistance (TCR): ± 20ppm/°C Max2. (– 55°C to + 150°C Ref. @ 25°C); Through the wiper3; ± 50ppm/°C • Load Life Stability: 0.1% Typical ∆R, 1.0% Maximum ∆R under Full Rated Power @ + 85°C for 1000 Hours Product may not be to scale • Settability: 0.1% • Setting Stability: 0.1% Typical1; 0.5% Maximum1, ∆SS • Power Rating4: 0.25 watts @ + 85°C • Resistance Range: 20Ω to 5KΩ • Resistance Tolerance: ± 10% TABLE 1 - MODEL SELECTION * MODEL 1268 TERMINATION STYLE AVERAGE WEIGHT (g) STANDARD RESISTANCE VALUES STANDARD POWER RATING @ NO. OF (in Ω) TOLERANCES + 85°C AMBIENT TURNS W-Edge Mount, Top Adjust 20, 50, 100, 200, 500, 1K 2K, 5K 0.4 X-Edge Mount, Side Adjust ± 10% 21 ± 2 0.25W *See Figure 1, next page. 2. Maximum TCR applies to the 3 σ (sigma) limit or 99.73% of a production lot. (Measured end-to-end with wiper off the element.) 3. Measurements of TCR through the wiper are influenced more by setting stability and the percentage of the total resistance in use (at the wiper) than by fundamental resistance change due to temperature alone. The parameter shown is a 2 σ distribution typifying the behavior of the device when used with 40% or more of the total resistance in use. 4. Derated linearly from full power @ + 85°C to zero (0) watts @ + 150°C. See Figure 2, next page. 5. Independent of resistance value 3 ohms maximum available on special request. Special Available Options: Special marking Burn-in and screening operations ADDITIONAL SPECIFICATIONS: TABLE 2 - ORDERING INFORMATION - 1268 SERIES PARTS • Contact Resistance Variation – CRV (noise): 10 ohms Maximum5 Please specify Vishay Model 1268 Precision Trimming Potentiometers as follows: • Hop-off: 0.25% Typical; 1.0% Maximum Example: • Operating Temperature Range: – 55°C to + 150°C • Adjustment Turns: 21 ± 2 • Mechanical Stops: Wiper Idles – No Discontinuity VISHAY FOIL • FRANCE +33.4.93.37.28.24 FAX: +33.4.93.37.27.31 • GERMANY +49.9287.710 FAX: +49 9287.70435 • ISRAEL +972.3.557.0945 FAX: +972.3.558.9121 Document Number: 63059 Revision 06-Aug-02 1268 W 100R 10% MODEL NO. TERMINATION STYLE RESISTANCE VALUE TOLERANCE See Table 1 for details. See Figure 1, next page for Standard Marking. • ITALY + 39.2.300.11919 FAX: +39.2.300.11999 • JAPAN +81.42.729.0661 FAX: +81.42.729.3400 • SINGAPORE +65.788.6668 FAX: +65.788.0988 • SWEDEN +46.8.594.70590 FAX: +46.8.594.70581 • UK +44 191 514 8237 FAX: +44 1953 457 722 • USA +1 610 407-4800 FAX: +1 610 640-9081 www.vishay.com 161 TRIMMERS NOTES: 1. Maximum is 1.0% A.Q.L. standard for all specifications except TCR. (For TCR information see notes 2 and 3). “Typical” is a designers reference which represents that 85% of the lots supplied, over a long period of time, will be at least the figure stated or better. 1268 Bulk Metal® Foil Technology Precision Trimming Potentiometers Vishay Foil Resistors FIGURE 1 - SCHEMATIC AND DIMENSIONS in inches (millimeters) 1268W 0.081 ±0.010" (2.08 ±0.25mm) 0.080" (2.03mm) MAX MAXIMUM VISHAY 0.420" (10.67mm) MAXIMUM MAX 2 CW 0.015" (0.38mm) MIN MINIMUM 0.300" (7.62mm) MIN MINIMUM 3 1 3 PINS 0.024 ±0.006" (0.61 ±0.15mm) DIA DIAMETER STANDARD MARKING Model No. Date Code Resistance Value Tolerance 0.090 ±0.005" (2.29 ±0.13mm) DIA 0.170 ±0.025" (4.32 ±0.64mm) ±0.010" (±0.25mm) C 0.100 ±0.005" (2.54 ±0.13mm) 0.075 ±0.010" (1.91 ±0.25mm) 0.375 ±0.015" (9.53 ±0.38mm) 0.187 ±0.020" (4.75 ±0.51mm) NOTES Adjustment screw 0.090 Inches (2.30mm) diameter with 0.020 Inches (0.51mm) x 0.031 Inches (0.80mm) slot. Model 1268 has solder plated copper terminal pins. 0.024 Inches (0.61mm) diameter, 0.300 Inches (7.62mm) length minimum. 0.080" (2.03mm) MAX MAXIMUM 1268X 0.081 ±0.010" (2.08 ±0.25mm) VISHAY 0.420" (10.67mm) MAX 2 MAXIMUM CW 0.300" (7.62mm) MIN MINIMUM 1 3 3 PINS 0.024 ±0.006" (0.61 ±0.15mm) DIA DIAMETER 0.075 ±0.010" (1.91 ±0.25mm) 0.170 ±0.025" (4.32 ±0.64mm) ±0.010" (±0.25mm) C 0.100 ±0.005" (2.54 ±0.13mm) 0.375 ±0.015" (9.53 ±0.38mm) 0.187 ±0.020" (4.75 ±0.51mm) 0.090 ±0.005" (2.29 ±0.13mm) DIA FIGURE 2 - POWER DERATING CURVE Percent of Rated Power TRIMMERS 0.015" (0.38mm) MIN MINIMUM +85°C +100 +75 +50 +25 0 -75 -50 -25 0 +25 +50 +75 +100 +125 +150 +175 Ambient Temperature °C VISHAY FOIL • FRANCE +33.4.93.37.28.24 FAX: +33.4.93.37.27.31 • GERMANY +49.9287.710 FAX: +49 9287.70435 • ISRAEL +972.3.557.0945 FAX: +972.3.558.9121 www.vishay.com 162 • ITALY + 39.2.300.11919 FAX: +39.2.300.11999 • JAPAN +81.42.729.0661 FAX: +81.42.729.3400 • SINGAPORE +65.788.6668 FAX: +65.788.0988 • SWEDEN +46.8.594.70590 FAX: +46.8.594.70581 • UK +44 191 514 8237 FAX: +44 1953 457 722 • USA +1 610 407-4800 FAX: +1 610 640-9081 Document Number: 63059 Revision 06-Aug-02 This datasheet has been download from: www.datasheetcatalog.com Datasheets for electronics components.