VPG Military & Space

Military and Space

For applications that require a high level of reliability, MIL style testing consisting of electrical and environmental stresses are added to the production process of the resistors in order to screen out and identify any parts or lots that exhibit variations in their performances. The level of testing that is required for specific applications is dependent on how critical the circuit is to the overall objective of the project. The testing of the parts may vary depending on the requirements of the specification; however the tests are usually separated into groups, some of which are screening tests performed on 100% of a production lot, while other lots are destructive tests that are performed on a sample of units from within a specific lot in order to guarantee the performance of the rest of the lot.
The Defense Supply Center of Columbus, DSCC, maintains a collection of qualified military specifications, the combined of which comprise a Qualified Parts List, or QPL. In order to be qualified to supply parts to a MIL spec, continuous testing of the production process is performed, and the results submitted to DSCC for approval. A third party review of the performances of the product line allows for the identification of variations in the production processes which may affect the performances of the product, guaranteeing consistency regardless of the date of manufacture of a QPL component. One of the higher levels of MIL spec require a constant calculation of failure rates based on the amount of parts which are tested. These specifications, known as Established Reliability or ER level parts, are guaranteed to perform below a specified failure rate. For example, the RNC90 resistor series made by Vishay Foil Resistors is qualified to be better than 0.01% per 1000 hours failure rate.
For applications used in space projects, a more specific and relevant testing pattern that was developed by NASA may be used as a basis. The EEE-INST-002 guidelines, or Instruction for EEE Parts Selection, Screening, Qualification, and Derating, are used as a basis for the development of several specifications which use foil resistors. By subjecting the resistors to the mentioned sequence of tests, the confidence level of a part to perform in a critical space application is improved. NASA developed the EEE-INST-002 guidelines to be flexible enough to accept any technology and part type, for which Vishay Foil Resistors has responded to with 5 specifications suggested for these types of critical projects.
Some military applications require either less stringent tests, or a part which is not qualified to a QPL specification. The Defense Supply Center of Columbus also maintains several up-screening plans oriented around products with high demand that have not been QPL qualified. These specifications, known as DSCC specs, consist of a 100% screening test, known as Group A testing, and also a destructive series of tests known as Group B testing. DSCC specifications are easily recognized by engineers, distributors, and QA organizations, and come in a wide variety of part types.
For each level of testing required, our resistors are able to be tested to the desired specification. By having Vishay Foil Resistors test and supply qualification conformance inspection data relevant to each specific lot, the end-user is guaranteed that the resistors supplied with every lot meet the original design parameters for the relevant application.


DSCC, EEE, EPPL ESA and CECC

TYPE CONSTRUCTION DSCC (1)
& MIL Spec#
EEE-INST-002 (2)
& MIL Spec#
EPPL (3) ESA (4) CECC (5) TYPICAL TCR MIL RANGE (ppm/°C) TYPICAL LOAD LIFE STABILITY 2000h
PRND Custom Hermetically Sealed Precision Resistor Network Device PRND EEE MIL-PRF-83401 2 0.05%
VSMP0805 Wrap around Surface Mount 07024
MIL-PRF-55342
303134
MIL-PRF-55342
0.2 0.005%
VSMP1206 07025
MIL-PRF-55342
303135
MIL-PRF-55342
VSMP1506 03010
MIL-PRF-55342
303136
MIL-PRF-55342
VSMP2010 06001
MIL-PRF-55342
303137
MIL-PRF-55342
VSMP2512 06002
MIL-PRF-55342
303138
MIL-PRF-55342
VSM0805 07024
MIL-PRF-55342
2
VSM1206 07025
MIL-PRF-55342
VSM1506 03010
MIL-PRF-55342
VSM2010 06001
MIL-PRF-55342
VSM2512 06002
MIL-PRF-55342
VSM2018 93030
MIL-PRF-55342
0.2
SMR1DZ Molded,flexible terminations with robust construction 06020
MIL-PRF-55182
303139
MIL-PRF-55182
0.2
SMR1D 06020
MIL-PRF-55182
2
SMR3DZ 06021
MIL-PRF-55182
303140
MIL-PRF-55182
0.2
SMR3D 06021
MIL-PRF-55182
2
VCS1625Z Current sence with Kelvin connections for high accuracy 08003
MIL-PRF-55342
303119Z
MIL-PRF-55342
0.2
VCS1625 00803
MIL-PRF-55342
303119
MIL-PRF-55342
2
CSM2512 07011
MIL-PRF-49465
303144
MIL-PRF-49465
15 Max 0.05%
CSM3637 07012
MIL-PRF-49465
303145
MIL-PRF-49465
Z201 Through hole 303143
S-311-P813
0.2 2
Z201L 303143L
S-311-P813
RCK HR 02, 02A 2 0.005 %
RS92N, RS92NA, AN 2 0.005 %
S102 89039
MIL-PRF-89039
2 0.005 %
300144 Through hole Voltage divider 87026
MIL-PRF-55182
2 0.005 %
300144Z 87026
MIL-PRF-55182
0.2
1240 Trimmer 87126
MIL-PRF-39035
10 0.1%

Notes:
(1) DSCC (Defense Supply Center Columbus)
(2) EEE-INST-002 (Instruction for EEE Parts Selection, Screening, Qualification, and Derating)
(3) EPPL (European Preferred Parts List)
(4) ESA -European Space Agency
(5) CENELEC Electronic Components Committee-European Committee for Electrotechnical Standardization
• All the above resistors are also available on the shelf as standard products


Established Reliability (ER)
The RNC90Y established reliability resistor has been the benchmark for high precision established reliability discrete resistors since 1982. In 2000, we achieved a technological breakthrough with the introduction of the Z201 resistor with a TCR of 0.2 PPM/°C. This breakthrough has allowed Vishay Precision Group to introduce the RNC90Z established reliability “R” level resistor, with a TCR limit of ± 2ppm/°C over the extended range of – 55°C to + 175°C, this being a significant improvement over the existing RNC90Y’s ± 5ppm/°C TCR specification.
Model Failure Rate Mil Spec No. Resistance Range (Ω) TCR(-25°C To +125°C Ref) Absolute Tolerance Termination Type
RNC90Y LEVEL R MIL PRF 55182/9 4R99-121K ±5 ppm/°C 0.005% Lead
RNC90T*
RNC90Z 30R1-121K ±2 ppm/ºC 0.005%
RNC90S*
*0.200” lead spacing
QPL
Vishay Foil resistors Models 1445Q and 1446Q networks are qualified to MIL-PRF-83401, Characteristic C,
Schematic A. Actual performance exceeds all the requirements of MIL-PRF-83401 characteristics “C.”
Model Mil Spec No. Resistance Range (Ω) TCR(-25°C To +125°C Ref) Absolute Tolerance Termination Type
1445Q MIL PRF 83401 100R-10K 100R -1K :±10 ppm/ºC1K – 10K:±5 ppm/ºC 0.1% 14 Pin DIP
1446Q 16 Pin DIP
Vishay Foil resistors model RJ26 Precision Trimming ¼ inch Potentiometer is qualified to Mil-PRF-22097
Model Mil Spec No. Resistance Range (Ω) TCR(-25°C To +125°C Ref) Absolute Tolerance Setability Termination Type
RJ26 MIL PRF 22097 50R,100R,200R,500R,1K,2K,5K ±25 ppm/°C 10% 0.05% Leaded

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