Document Number: 63052 For any questions, contact: foil@vishay.com
www.vishay.com
Revision: 06-Nov-08 3
1242
Bulk Metal
®
Foil Technology
Precision Trimming Potentiometers, QPL Approved 1/4 Inch
Square, Qualified to MIL-PRF-22097, Char. F, RJ26
Vishay Foil Resistors
Notes
1. 5 Ω, 10 Ω, and 20 Ω resistance values available on special order.
2. 5 % resistance tolerance available on special order.
3. Maximum is 1.0 % A.Q.L. standard for all specifications except TCR. (For TCR information, see notes 4 and 5.) “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 shown or better.
4. 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.)
5. 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.
6. Derated linearly for full power at + 85 °C to zero (0) W at + 150 °C. See figure 2 on previous page.
7. Whichever is greater.
8. All ΔR’s are measured to the tolerance specified + 0.01 Ω.
TABLE 4 - COMPARISON
MIL-PRF-22097/5 CHARACTERISTIC F
8)
(RJ26) 1242 SPECIFICATIONS
TEST GROUP I
Visual and mechanical No failures No failures
Total resistance ± 10 % ± 10 %
Actual effective electrical travel 10 to 25 turns 21 ± 2 turns
End resistance ± 2 % or 20 Ω
7)
2 Ω (values ≤ 1 kΩ) ; 5 Ω (values ≥ 2 kΩ)
Contact resistance variation - CRV (noise) ± 3.0 % or 3 Ω
7)
± 3.0 % or 3 Ω
7)
Dielectric withstanding voltage - DWV Per MIL-STD-202, methods 301 and 105 Per MIL-STD-202, methods 301 and 105
(atmospheric and barometric pressure)
Insulation resistance > 1000 MΩ > 1000 MΩ
Shaft torque 3 oz. in. maximum 3 oz. in. maximum
Thermal shock ± 1.0 % 0.1 % typical; 0.5 % maximum
TEST GROUP II
Resistance temperature characteristic - TCR ± 0.01 % (± 100 ppm/°C) ± 0.001 % (10 ppm/°C)
Moisture resistance ± 1.0 % ± 0.5 %
Contact resistance variation - CRV (noise) ± 3.0 % or 3 Ω
7)
± 3.0 % or 3 Ω
7)
TEST GROUP III
Shock (specified pulse) ± 1.0 % ± 0.5 %
Vibration (high-frequency) ± 1.0 % ± 0.5 %
Contact resistance variation - CRV (noise) ± 3.0 % or 3 Ω
7)
± 3.0 % or 3 Ω
7)
Salt spray No corrosion No corrosion
TEST GROUP IV
Solder heat ± 1.0 % ± 0.1 %
Life (1000 h at 85 °C) ± 2.0 % ± 1.0 %
Contact resistance variation - CRV (noise) ± 3.0 % or 3 Ω
7)
± 3.0 % or 3 Ω
7)
TEST GROUP V
Low-temperature operation ± 1.0 % ± 0.5 %
High-temperature exposure ± 2.0 % ± 0.5 %
Contact resistance variation - CRV (noise) ± 3.0 % or 3 Ω
7)
± 3.0 % or 3 Ω
7)
TEST GROUP VI
Rotational life ± 2.0 % ± 2.0 %
Contact resistance variation - CRV (noise) ± 3.0 % or 3 Ω
7)
± 3.0 % or 3 Ω
7)
Terminal strength 2 lbs. 2 lbs.
TEST GROUP VII
Solderability MIL-STD-202 method 208 MIL-STD-202 method 208
Immersion No continuous stream of bubbles No continuous stream of bubbles
TEST GROUP VIII MIL-STD-810 method 508 MIL-STD-810 method 508
Fungus No mechanical damage No mechanical damage
