MIL-PRF-20 Capacitor, Fixed, Ceramic Dielectric \(Temperature Compensating\), Established Reliability And Non-Established Reliability, General Specification ForThis specification covers the general requirements for established reliability \(ER\) and non-ER, temperature compensating, fixed capacitors for use primarily where compensation is necessary for circuit applications due to temperature changes, in bypass and coupling applications. Capacitors meeting the ER requirements specified herein have a failure rate level \(FRL\) ranging from 1.0 percent per 1,000 hours to 0.00l percent per 1,000 hours. These failure rate levels are established at a 90-percent confidence level based on the life test parameters specified and are maintained at a 10-percent producer\'s risk. An acceleration factor of 8:1 has been used to relate the life test data at 200 percent of rated voltage at the applicable high test temperature to the rated voltage at the applicable high test temperature. A part per million \(ppm\) quality system is used for documenting and reporting the average outgoing quality of ER capacitors supplied to this specification. Statistical process control \(SPC\) techniques are required in the manufacturing process to minimize variation in production of ER capacitors supplied to the requirements of this specification.

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MIL-PRF-20M

b. Test temperature: At the applicable elevated test temperature, �3�C (see 3.1).

c. Operating conditions: One of the following conditions as specified (see 3.1).

Condition 1: Capacitors shall be subjected to the dc potential equal to a minimum of 150 percent of the dc

rated voltage on which an alternating-current rms potential (60 Hz �2 Hz) equal to a minimum of

50 percent of dc rated voltage is superimposed.

Condition 2: Capacitors shall be subjected to the dc potential equal to a minimum of 200 percent of the dc

rated voltage. Current shall be equal to 30mA to 50 mA.

F, �24 hours

d. Test condition:

ER:

D, �12 hours.

Non-ER:

e. Examination and measurements after exposure: Capacitors shall be returned to the inspection conditions

specified in 4.3, and shall be visually examined for evidence of corrosion and mechanical damage; the

capacitance, dissipation factor, and insulation resistance shall be measured as specified in 4.7.3, 4.7.4, and

4.7.7.1, respectively.

4.7.20.2 For conformance inspection. Capacitors shall be tested as specified in 4.7.20.1, except that duration of

test will be 2,000 hours +96 hours, -0 hours for ER styles and 1000 hours +48 hours, -0 hours for non-ER styles.