Bulk Metal
®
Foil Technology Ultra High Precision Trimming Potentiometers,
1
/
4
" Square, RJ26 Style, Designed to Meet or Exceed The Requirements of
MIL-PRF-39035, Char. H with a Smooth and Unidirectional Output
Document Number: 63053 For any questions, contact: foil@vishay.com www.vishay.com
Revision: 26-Mar-09 1
Accutrim™ 1240 (RJ26 Style)
Vishay Foil Resistors
INTRODUCTION
Vishay Foil precision trimmers have the Bulk Metal® Foil
resistive element which possesses a unique inherent
temperature and load life stability. Plus, their advanced
virtually back lash-free adjustment mechanism makes them
easy to set quickly and accurately and keeps the setting
exactly on target.
FEATURES
•Temperature coefficient of resistance (TCR):
± 10 ppm/°C. (- 55 °C to + 150 °C ref. at + 25 °C);
through the wiper (3); ± 25 ppm/°C (see table 2 for
low values)
•A smooth and unidirectional resistance with
leadscrew adjustment
•Load life stability: 0.1 % typical ΔR, 1.0 % maximum ΔR
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
•Power rating: 0.25 W at + 85 °C
•Resistance range: 5 Ω to 10 kΩ
•Tolerance: ± 5 %, ± 10 %
•Electrostatic discharge (ESD) up to 25 000 V
•Terminal finish: gold plated (tin/lead finish is available on
request)
Note
• See Figure 1, next page
1240P 1240W1240X
CERMET
Wiper Travel
Resistance
Wiper Travel
Resistance
BULK METAL
FOIL WIREWOUND
Wiper Travel
Resistance
TABLE 1 - MODEL SELECTION
MODEL TERMINATION STYLE AVERAGE WEIGHT (g) POWER RATING at + 85 °C AMBIENT NO. OF TURNS
1240
W-edge mount, top adjust
0.4 0.25 W 21 ± 2X-edge mount, side adjust
P-horizontal mount, side adjust
TABLE 2 - 1240 (RJ26) SERIES
ELECTRICAL SPECIFICATIONS
Temperature Coefficient of
Resistance (TCR) 50 Ω to 10 kΩ
± 10 ppm/°C maximum
(- 55 °C to + 150 °C,
+ 25 °C ref.)
End-to-end (2)
Temperature Coefficient of
Resistance 5, 10 and 20 Ω± 20 ppm/°C
Through the wiper (3) ± 25 ppm/°C
Stability
Load life at 10 000 h
End-to-end (2)
0.1 % typical ΔR
1.0 % maximum ΔR
(under full rated power of
0.25 W at + 85 °C)
Power Rating (4) 0.25 W at + 85 °C
Settability 0.05 % typical;
0.1 % maximum
Setting Stability 0.1 % typical;
0.5 % maximum
Contact Resistance
Variation - CRV (noise) (5) 3 Ω typical;
10 Ω maximum
Hop-off 0.25 % typical;
1.0 % maximum
High-Frequency Operation
Rise time
Inductance
Capacitance
1.0 ns without ringing
0.08 µH typical
0.5 pF typical
Operating Temperature Range - 55 °C to + 150 °C
TABLE 3 - VALUES VS. TOLERANCES
STANDARD RESISTANCE VALUES
(in Ω)
STANDARD
TOLERANCE
5, 10 ± 10 %
20, 50, 100, 200, 500, 1K, 2K, 5K, 10K ± 5 %
TABLE 4 - MECHANICAL SPECIFICATIONS
Adjustment Turns
21 ±
2
Mechanical Stops
Wiper idles - no discontinuity
Internal
Terminations
All welded - no flux
Case Material
1240X - diallyl-phthalate: green (DAP)
1240W - diallyl-phthalate: green (DAP)
1240P - thermoplastic: black
Shaft Torque
3 oz. in. maximum
Backlash
0.005 % typical
Accutrim™ 1240 (RJ26 Style)
Vishay Foil Resistors
www.vishay.com For any questions, contact: foil@vishay.com Document Number: 63053
2Revision: 26-Mar-09
FIGURE 1 - SCHEMATIC AND DIMENSIONS in Inches (Millimeters)
TOLERANCES:
A = ± 0.005" (0.13 mm)
C = ± 0.010" (0.25 mm)
D = ± 0.020" (0.51 mm)
STANDARD MARKING:
Model No.
Date Code
Resistance Value
Tolerance
NOTES:
Adjustment screw 0.080" (2.03 mm) diameter with
0.025" (0.64 mm) X 0.030" (0.76 mm) slot. Tolerance on
screw dimensions is ± 0.005" (0.13 mm). Model 1240
has gold plated terminal pins 0.016" (0.41 mm) ± 0.001"
(0.03 mm) diameter, 0.200" (5.08 mm) length minimum.
1240X
0.050" (1.27 mm) C
0.040" (1.02 mm) C
VISHAY
2
3
1
CW
0.250" (6.35 mm) D
123
0.250" (6.35 mm) D
0.100" (2.54 mm) A
0.100" (2.54 mm) A
0.050" (1.27 mm) C
0.050" (1.27 mm) C
0.175" (4.45 mm) C
0.125" (3.18 mm) C
(bottom view)
1240W
3 12
0.050" (1.27 mm) C
VISHAY
2
13
CW
0.250" (6.35 mm) D
0.250" (6.35 mm) D
0.100" (2.54 mm) A
0.100" (2.54 mm) A
0.050" (1.27 mm) C
0.050" (1.27 mm) C
0.175" (4.45 mm) C
0.125" (3.18 mm) C
0.040" (1.02 mm) C
0.010" (0.25 mm) A
(bottom view)
Resistance
Value
Tolerance
0.055" (1.40 mm) C
0.050" (1.27 mm) C
VISHAY
3
1
CW
0.175" (4.45 mm) C
12 3
0.250" (6.35mm) D
0.100" (2.54 mm) A
0.100" (2.54 mm) A
0.035" (0.89 mm) C
0.250" (6.35 mm) D
0.125" (3.18 mm) C
Model No.
Date Code
0.016"
(0.41 mm) A
1240P
FIGURE 2 - POWER DERATING CURVE
Ambient Temperature °C
+ 85 °C
+ 100
+ 75
+ 50
+ 25
0
Percent of Rated Power
- 75 + 150+ 125+ 100+ 75+ 50+ 250- 25- 50 + 175
FIGURE 3 - 1240W 10 k
Ω
LOAD LIFE, 20 UNITS,
10 000 h at 0.25 W, + 85 °C (Wiper at CW)
+ 2000
+ 1500
+ 1000
+ 500
0
- 500
- 1000
- 1500
- 2000
ΔR/R (ppm)
Time (h)
0 2000 4000 8000 10 0006000
Document Number: 63053 For any questions, contact: foil@vishay.com www.vishay.com
Revision: 26-Mar-09 3
Accutrim™ 1240 (RJ26 Style)
Vishay Foil Resistors
Notes
(1) Maximum is 1.0 % A.Q.L. standard for all specifications except
TCR. (For TCR information, see notes 2 and 3.)
(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 in table 2 is a 2 s
distribution typifying the behavior of the device when used with
40 % or more of the total resistance in use.
(4) Derated linearly for full power at + 85 °C to zero power at
+ 150 °C. See Figure 2 on previous page.
(5) Independent of resistance value. 3 Ω maximum available on
special request.
(6) All ΔR’s are measured to the tolerance specified + 0.01 Ω.
(7) Whichever is greater.
Special Available Options:
Special marking
Burn-in and screening operations.
VISHAY TRIMMERS ARE INSPECTED
100 % for:
•Immersion
• Resistance tolerance check
• End resistance
• Visual-mechanical
• Dynamic tests for continuity, CRV
By sample for:
•TCR
•DWV
TABLE 5 - COMPARISON
MIL-PRF-39035/3 CHARACTERISTIC H (6) MODEL 1240 MAXIMUM
TEST GROUP I
Conditioning
Contact resistance variation - CRV (noise)
Immersion
± 1.0 %
± 3.0 % or 3 Ω (7)
No continuous stream of bubbles
± 0.5 %
3 Ω typical, 10 Ω maximum
No continuous stream of bubbles
TEST GROUP I a
Visual and mechanical
Actual effective electrical travel
End resistance
Dielectric withstanding voltage - DWV
Per MIL-STD-202, methods 301 and 105
Atmospheric pressure
Barometric pressure
Insulation resistance
Shaft torque
Thermal shock
Setting stability
No failures
10 to 25 turns
2 % or 2 Ω (7)
600 VAC, 1 min
250 VAC, 1 min
≥ 1000 MΩ
3 oz. in. maximum
± 1.0 %
± 1.0 %
No failures
21 ± 2 turns
2 Ω for values ≤ 1 kΩ;
5 Ω for values ≥ 2 kΩ;
600 VAC, 1 min
250 VAC, 1 min
> 1000 MΩ
3 oz. in. maximum
± 0.5 %
± 0.5 %
TEST GROUP II
Solderability Per MIL-STD-202, method 208 Per MIL-STD-202, method 208
TEST GROUP III
Resistance temperature characteristic - TCR
Moisture resistance
Contact resistance variation - CRV (noise)
± 0.005 %/°C (± 50 ppm/°C)
± 1.0 %
3.0 % or 3 Ω (7)
± 0.001 %/°C (± 10 ppm/°C)
± 0.5 %
3 Ω typical, 10 Ω maximum
TEST GROUP IV
Settability
Shock
Setting stability
Vibration
Setting stability
Contact resistance variation - CRV (noise)
Salt spray
± 1.0 %
± 1.0 %
± 1.0 %
± 1.0 %
± 1.0 %
3.0 % or 3 Ω (7)
No corrosion
± 0.1 %
± 0.5 %
± 0.5 %
± 0.5 %
± 0.5 %
3 Ω typical, 10 Ω maximum
No corrosion
TEST GROUP V
Solder heat
Low-temperature operation
Setting stability
Low-temperature storage
High-temperature exposure
Setting stability
Contact resistance variation - CRV (noise)
Integrity of shaft
± 1.0 %
± 1.0 %
± 2.0 %
± 1.0 %
± 3.0 %
± 2.0 %
3 % or 3 Ω (7)
No loosening or breakage
± 0.1 %
± 0.5 %
± 0.5 %
± 0.5 %
± 0.5 %
± 0.5 %
3 Ω typical, 10 Ω maximum
No loosening or breakage
TEST GROUP VI
Rotational life (200 cycles)
Contact resistance variation - CRV (noise)
Terminal strength
± 2.0 %
3 % or 3 Ω (7)
2 lbs.
± 2.0 %
3 Ω typical, 10 Ω maximum
2 lbs.
TEST GROUP VII
Life (2000 h) at + 85 °C
Life (10 000 h) at + 85 °C
± 3.0 %
± 5.0 %
± 0.1 % typical, ± 1.0 % maximum
± 0.1 % typical, ± 1.0 % maximum
TEST GROUP VIII
Solvent resistance No failures No failures
Accutrim™ 1240 (RJ26 Style)
Vishay Foil Resistors
www.vishay.com For any questions, contact: foil@vishay.com Document Number: 63053
4Revision: 26-Mar-09
Note
(1) For non-standard requests, please contact application engineering.
TABLE 6 - GLOBAL PART NUMBER INFORMATION
NEW GLOBAL PART NUMBER: Y4053500R000J0L (preferred part number format)
DENOTES PRECISION VALUE CHARACTERISTICS (1)
YR = Ω
K = kΩ
0 = gold plated termination (lead (Pb)-free)
1 to 999 = custom
PRODUCT CODE TOLERANCE PACKAGING
4053 = 1240W
5053 = 1240X
0053 = 1240P
J= ± 5 %
K= ± 10 %
L = foam/box pack
FOR EXAMPLE: ABOVE GLOBAL ORDER Y4053 500R000 J 0 L:
TYPE: 1240W
VALUE: 500.0 Ω
ABSOLUTE TOLERANCE: ± 5.0 %
TERMINATION: gold plated termination (lead (Pb)-free)
PACKAGING: foam/box pack
HISTORICAL PART NUMBER: 1240W 500R00 J B (will continue to be used)
1240W 500R00 J B
MODEL RESISTANCE VALUE TOLERANCE PACKAGING
1240W
1240X
1240P
500R00 = 500.0 ΩJ= ± 5 %
K= ± 10 %
B = foam/box pack
0535 0R00Y4 J00 L0
Document Number: 91000 www.vishay.com
Revision: 18-Jul-08 1
Disclaimer
Legal Disclaimer Notice
Vishay
All product specifications and data are subject to change without notice.
Vishay Intertechnology, Inc., its affiliates, agents, and employees, and all persons acting on its or their behalf
(collectively, “Vishay”), disclaim any and all liability for any errors, inaccuracies or incompleteness contained herein
or in any other disclosure relating to any product.
Vishay disclaims any and all liability arising out of the use or application of any product described herein or of any
information provided herein to the maximum extent permitted by law. The product specifications do not expand or
otherwise modify Vishay’s terms and conditions of purchase, including but not limited to the warranty expressed
therein, which apply to these products.
No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this
document or by any conduct of Vishay.
The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications unless
otherwise expressly indicated. Customers using or selling Vishay products not expressly indicated for use in such
applications do so entirely at their own risk and agree to fully indemnify Vishay for any damages arising or resulting
from such use or sale. Please contact authorized Vishay personnel to obtain written terms and conditions regarding
products designed for such applications.
Product names and markings noted herein may be trademarks of their respective owners.
