Accutrim 1240 (RJ26 Style) Vishay Foil Resistors Bulk Metal Foil Technology Ultra High Precision Trimming Potentiometers, 1 / Square, RJ26 Style, Designed to Meet or Exceed The Requirements of 4 MIL-PRF-39035, Char. H with a Smooth and Unidirectional Output FEATURES Temperature coefficient of resistance (TCR): 10 ppm/C. (- 55 C to + 150 C ref. at + 25 C) (3) through the wiper 25 ppm/C (see table 2 for low values) A smooth and unidirectional resistance with leadscrew adjustment Load life stability: 0.1 % typical R, 1.0 % maximum R under full rated power at + 85 C for 10 000 h Settability: 0.05 % typical 0.1 % maximum Setting stability: 0.1 % typical 0.5 % maximum, DSS INTRODUCTION Power rating: 0.25 W at + 85 C Vishay Foil Resistors (VFR) precision trimmers have the Resistance range: 5 to 10 k Bulk Metal Foil resistive element which possesses a unique Tolerance: 5 %, 10 % inherent temperature and load life stability. Plus, their Electrostatic discharge (ESD) at least to 25 kV advanced virtually back lash-free adjustment mechanism Terminal finish: gold plated (tin/lead finish is available on makes them easy to set quickly and accurately and keeps request) the setting exactly on target. BULK METAL WIREWOUND CERMET FOIL Wiper Travel Wiper Travel Wiper Travel TABLE 1 - MODEL SELECTION MODEL TERMINATION STYLE AVERAGE WEIGHT (g) POWER RATING at + 85 C AMBIENT NO. OF TURNS W-edge mount, top adjust 1240 X-edge mount, side adjust 0.4 0.25 W 21 2 P-horizontal mount, side adjust Note See Figure 1, next page TABLE 2 - 1240 (RJ26) SERIES TABLE 3 - VALUES VS. TOLERANCES ELECTRICAL SPECIFICATIONS STANDARD RESISTANCE VALUES STANDARD Temperature Coefficient of 10 ppm/C maximum (in ) TOLERANCE Resistance (TCR) 50 to 10 k (- 55 C to + 150 C, + 25 C ref.) (2) End-to-end 5, 10 10 % Temperature Coefficient of Resistance 5, 10 and 20 20 ppm/C 20, 50, 100, 200, 500, 1K, 2K, 5K, 10K 5 % (3) Through the wiper 25 ppm/C Stability 0.1 % typical R 1.0 % maximum R Load life at 10 000 h (2) (under full rated power of End-to-end TABLE 4 - MECHANICAL SPECIFICATIONS 0.25 W at + 85 C) (4) Power Rating 0.25 W at + 85 C Adjustment Turns 21 2 Settability 0.05 % typical 0.1 % maximum Mechanical Stops Wiper idles - no discontinuity Setting Stability 0.1 % typical 0.5 % maximum Internal All welded - no flux Terminations Contact Resistance 3 typical (5) Variation - CRV (noise) 10 maximum 1240X - diallyl-phthalate: green (DAP) Hop-off 0.25 % typical Case Material 1240W - diallyl-phthalate: green (DAP) 1.0 % maximum 1240P - thermoplastic: black High-Frequency Operation Rise time 1.0 ns without ringing Shaft Torque 3 oz. in. maximum Inductance 0.08 H typical Capacitance 0.5 pF typical Backlash 0.005 % typical Operating Temperature Range - 55 C to + 150 C Document Number: 63053 For any questions, contact: foil vishaypg.com www.vishayfoilresistors.com Revision: 16-Oct-13 1 Resistance Resistance ResistanceAccutrim 1240 (RJ26 Style) Vishay Foil Resistors FIGURE 1 - SCHEMATIC AND DIMENSIONS in Inches (Millimeters) 1240X 1240W 0.050 (1.27 mm) C 0.040 (1.02 mm) C 0.040 (1.02 mm) C VFR 2 0.250 (6.35 mm) D 0.250 (6.35 mm) D VFR CW 1 3 3 1 CW 2 3 2 1 1 2 3 0.250 (6.35 mm) D 0.250 (6.35 mm) D 0.050 (1.27 mm) C 0.050 (1.27 mm) C 0.010 (0.25 mm) A 0.050 (1.27 mm) C 0.175 (4.45 mm) C 0.100 (2.54 mm) A 0.100 (2.54 mm) A 0.175 (4.45 mm) C 0.050 (1.27 mm) C 0.050 (1.27 mm) C 0.100 (2.54 mm) A 0.100 (2.54 mm) A 0.125 (3.18 mm) C 0.125 (3.18 mm) C (bottom view) (bottom view) 1240P 0.050 (1.27 mm) C VFR 0.175 (4.45 mm) D CW TOLERANCES: STANDARD MARKING: 1 A = 0.005 (0.13 mm) Model No. 3 C = 0.010 (0.25 mm) Date Code D = 0.020 (0.51 mm) Resistance Value 1 2 3 Tolerance 0.250 (6.35mm) D 0.055 (1.40 mm) C NOTES: 0.035 (0.89 mm) C 0.016 (0.41 mm) A Adjustment screw 0.080 (2.03 mm) diameter with Resistance Value 0.025 (0.64 mm) X 0.030 (0.76 mm) slot. Tolerance on 0.100 (2.54 mm) A Tolerance 0.250 (6.35 mm) D screw dimensions is 0.005 (0.13 mm). Model 1240 0.125 (3.18 mm) C has gold plated terminal pins 0.016 (0.41 mm) 0.001 (0.03 mm) diameter, 0.200 (5.08 mm) length minimum. Model No. 0.100 (2.54 mm) A Date Code FIGURE 2 - POWER DERATING CURVE FIGURE 3 - 1240W 10 k LOAD LIFE, 20 UNITS, 10 000 h at 0.25 W, + 85 C (Wiper at CW) + 2000 + 85 C + 1500 + 100 + 1000 + 75 + 500 + 50 0 - 500 + 25 - 1000 0 - 75 - 50 - 25 0 + 25 + 50 + 75 + 100 + 125 + 150 + 175 - 1500 Ambient Temperature C - 2000 0 2000 4000 6000 8000 10 000 Time (h) www.vishayfoilresistors.com For any questions, contact: foil vishaypg.com Document Number: 63053 2 Revision: 16-Oct-13 Percent of Rated Power R/R (ppm)