1、 MIL-PRF-81F SUPERSEDING 5 May 2011 MIL-PRF-81E 15 December 2005 PERFORMANCE SPECIFICATION CAPACITORS, VARIABLE, CERAMIC DIELECTRIC, GENERAL SPECIFICATION FOR This specification is approved for use by all Department and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope6.1. This specification
2、 covers the general requirements for ceramic dielectric; variable capacitors intended for operation over a temperature range of -55C to +85C, for use in circuits where periodic adjustments are required (see ). 1.2 Classification. 1.2.1 Type of designation 3.1. The type designation is in the followin
3、g form, and as specified (see and 6.2). CV11 A 070 Style Characteristic Capacitance (1.2.1.1) (1.2.1.2) (1.2.1.3) 1.2.1.1 Style. The style is identified by the two-letter symbol “CV” followed by a two-digit number; the letters identify ceramic dielectric, variable capacitors and the number identifie
4、s the shape and dimensions of the capacitor. 1.2.1.2 Characteristic table I. The characteristic is identified by a single letter in accordance with . 1.2.1.3 Capacitance. The nominal maximum rated capacitance value expressed in picofarads (pF) is identified by a three-digit number; the first two dig
5、its represent significant figures and the last digit specified the number of zeros to follow. When fractional values are required, the letter “R” will be used to indicate the decimal point. For example: 2R5 indicates 2.5 pF. Comments, suggestions, or questions on this document should be addressed to
6、: DLA Land and Maritime ATTN:VAT, Post Office Box 3990, Columbus, OH 43218-3990 or emailed to capacitorfilterdla.mil .Since contact information can change, you may want to verify the currency of this address information using the ASSIST Online database at https:/assist.daps.dla.mil . AMSC N/A FSC 59
7、10 INCH POUND Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-81F 2 TABLE I. Characteristics. Capacitance change from value at 25C Symbol At -55C At +85C At +125C Minimum Maximum Minimum Maximum Minimum Maximum A B C D E G Percent -4.5 -1.0 -
8、1.0 +1.5 +3.0 0.0 Percent +2.0 +3.5 +6.5 +8.2 +14.0 +14.0 Percent -2.5 -2.5 -4.0 -5.0 -10.0 -8.0 Percent +2.0 -0.5 -1.0 -1.5 -3.0 -3.0 Percent -4.2 -4.2 -6.7 -8.5 -15.0 -14.0 Percent +3.4 -0.8 -1.7 -2.5 -9.0 -5.0 Temperature coefficient -55C to +85C F H J K L M N P Q +100 150 ppm/C +100 600 ppm/C -3
9、00 300 ppm/C -450 300 ppm/C +50 150 ppm/C -100 500 ppm/C -300 800 ppm/C -400 500 ppm/C -1500 900 ppm/C Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-81F 3 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specifi
10、ed in sections 3, 4 or 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that
11、they must meet all specified requirements of the documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this document
12、 to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-PRF-81/1- Capacitors, Variable, Ceramic Dielectric, Style CV11 MIL-PRF-81/4 - Capacitors, Variable, Ceramic Dielectric,
13、Styles CV31 and CV32 MIL-PRF-81/6 - Capacitors, Variable, Ceramic Dielectric, Styles CV35 and CV36 DEPARTMENT OF DEFENSE STANDARDS MIL-STD-202 - Test Methods for Electronic and Electrical Component Parts. (Copies of these documents are available online at https:/assist.daps.dla.mil/quicksearch/ or h
14、ttps:/assist.daps.dla.mil or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 1911-5094). 2.3 Order of precedence. In the event of a conflict between the text of this document and the references cited herein (except for related associated specifications
15、, specification sheets, or MS standards), the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 Specification sheets. The individual item requirements shall be as sp
16、ecified herein and in accordance with the applicable specification sheet. In the event of any conflict between the requirements of this specification and the specification sheet, the latter shall govern. 3.2 Qualification4.3. Capacitors furnished under this specification shall be products which are
17、authorized by the qualifying activity for listing on the applicable Qualified Products List (QPL) at the time of award of contract (see and 6.3). 3.3 Material. The material shall be as specified herein; however when a definite material is not specified, a material shall be used which will enable the
18、 capacitors to meet the performance requirements of this specification. Acceptance or approval of any constituent material shall not be construed as a guaranty of the acceptance of the finished product. 3.4 Interface and physical dimensions3.1. Capacitors shall meet the interface, and physical dimen
19、sions specified (see ). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-81F 4 3.4.1 Pure tin6.7. The use of pure tin as an underplate or final finish is prohibited both internally and externally. Tin content of capacitor components and solder
20、 shall not exceed 97 percent by mass. Tin shall be alloyed with a minimum of 3 percent lead, by mass (see ). 3.5 Dielectric withstanding voltage 4.6.2. When measured as specified in , capacitors shall withstand the direct current (dc) potential without damage, breakdown, or flashover. 3.6 Barometric
21、 pressure (reduced, qualification only) 4.6.3. When measured as specified in , capacitors shall withstand the dc potential without breakdown or flashover. 3.7 Insulation resistance 4.6.4. When measured as specified in , the insulation resistance of the capacitors shall be not less than 10,000 megohm
22、s. 3.8 Capacitance 4.6.5. When measured as specified in , the minimum capacitance shall be no greater than the minimum value specified and the maximum capacitance shall be not less than the maximum value specified, and no greater than 50 percent above the maximum value specified (see 3.1). 3.9 Dissi
23、pation factor 4.6.6. When measured as specified in , the dissipation factor of capacitors shall be not more than 0.2 percent. 3.10 Temperature coefficient and capacitance drift. 3.10.1 Temperature coefficient 4.6.7.1. When measured as specified in , capacitance change measurements shall be within th
24、e limits specified in table I for the applicable characteristic. 3.10.2 Capacitance drift (for qualification only) 4.6.7.2. When calculated as specified in , capacitance drift shall be within 0.5 pF of the initial step 1 measurement. 3.11 Terminal strength 4.6.8. When measured as specified in , ther
25、e shall be no fracture, loosening of parts, or other mechanical failures. 3.12 Torque 4.6.9. When measured as specified in , the torque values shall be within the limits specified for individual capacitor styles (see 3.1). 3.13 Fatigue 4.6.10. When measured as specified in , capacitors shall meet th
26、e following requirements: Capacitance: Change not more than 12 percent or 0.75 pF, whichever is greater, from the initial value obtained when measured as specified in 4.6.10. Torque: As specified for individual capacitor styles (see 3.1). 3.14 Life 4.6.11. When tested as specified in , capacitors sh
27、all meet the following requirements: Insulation resistance: As specified in 3.7. Capacitance: Unless otherwise specified, change not more than 5 percent or 0.5 pF, whichever is greater, from the initial value obtained when set and measured as specified in 4.6.11.1. 3.15 Shock, specified pulse 4.6.12
28、. When capacitors are tested as specified in , there shall be no intermittent contacts of 0.5 millisecond (ms) or greater duration or arcing or other indication of breakdown, nor shall there be any open or short circuiting or evidence of mechanical damage. Provided by IHSNot for ResaleNo reproductio
29、n or networking permitted without license from IHS-,-,-MIL-PRF-81F 5 3.16 Vibration, high frequency 4.6.13. When capacitors are tested as specified in , there shall be no intermittent contacts of 0.5 ms or greater duration or arcing or other indication of breakdown, nor shall there be any open or sh
30、ort circuiting or evidence of mechanical damage. Capacitors shall also meet the following requirements. Capacitance: Change not more than 2 percent of 0.5 pF (0.25 pF for values less than 10 pF), whichever is greater, from the initial value obtained when measured as specified in 4.6.5. Dissipation f
31、actor: Not more than 0.2 percent. Dielectric withstanding voltage: As specified in 3.5. 3.17 Moisture resistance 4.6.14. When measured as specified in , capacitors shall meet the following requirements. Visual inspection: There shall be no mechanical damage. Insulation resistance: Shall exceed 10,00
32、0 megohms. Capacitance: Change not more than 10 percent for style CV11, and not more than 5 percent for style CV31 from the initial value obtained when set and measured as specified in 4.6.5. Dissipation factor: Shall not be more than 0.5 percent. 3.18 Marking. Each capacitor shall be legibly marked
33、 with smear-resistant ink that will withstand the environmental tests specified herein and shall be marked with the type designation, and the manufacturers name or symbol. The marking shall not be placed on the mounting surface. There shall be no space between the symbols which comprise the type des
34、ignation. If lack of space requires it, the type designation may appear on two lines. In this event, the type designation shall be divided between the style and the characteristic symbols and shall appear on two lines as shown in the following example. CV11 A070 Other markings which in any way inter
35、fere with, obscure, or confuse those specified herein, are prohibited. Marking shall remain legible after all tests. 3.19 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maximum extent possible provided
36、that the material meets or exceeds the operational and maintenance requirements, and promotes economically advantageous life cycle costs. 3.20 Workmanship. Capacitors shall be manufactured and processed in such a manner as to be uniform in quality and be free from other defects that will affect life
37、, serviceability, or appearance. 3.20.1 Soldering. All excess flux or solder shall be removed. Electrical connections shall be electrically continuous after soldering. 3.20.2 Finish of terminals. The terminals shall be so coated that soldering can be accomplished readily. Provided by IHSNot for Resa
38、leNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-81F 6 4. VERIFICATION 4.1 Classification of inspection. The inspection requirements specified herein are classified as follows: a. Qualification inspection (see 4.3). b. Conformance inspection (see 4.4). c. Periodic group
39、 C inspection (see 4.5). 4.2 Inspection conditionsMIL-STD-202. Unless otherwise specified herein, all inspections shall be performed in accordance with the “GENERAL REQUIREMENTS” of . Accuracy of all test voltage measurements shall be within 2.0 percent of the specified voltage. 4.3 Qualification in
40、spection6.3. Qualification inspection shall be performed at a laboratory acceptable to the Government (see ), on sample units produced with equipment and procedures normally used in production. 4.3.1 Sampletable II. The number of sample units comprising a sample of capacitors to be subjected to qual
41、ification inspection shall be as specified in or the appendix to this specification. TABLE II. Qualification inspection. Inspection Requirement paragraph Method paragraph Number of sample units to be tested Number of failures permitted 1/ Group I Visual and mechanical inspection: Design, constructio
42、n, and physical dimensions 3.1 and 3.4 4.6.1 2 1 Marking and workmanship 2/ Dielectric withstanding voltage Barometric pressure (reduced) Insulation resistance Capacitance Dissipation factor 3.18 to 3.20.2 inclusive 3.5 3.6 3.7 3.8 3.9 4.6.2 4.6.3 4.6.4 4.6.5 4.6.6 18 26 1 1 Temperature coefficient
43、and capacitance drift 3.10 4.6.7 6 1 Group II Terminal strength Torque Fatigue Life 3.11 3.12 3.13 3.14 4.6.8 4.6.9 4.6.10 4.6.11 12 1 Group III Shock, specified pulse Vibration, high frequency Moisture resistance 3.15 3.16 3.17 4.6.12 4.6.13 4.6.14 12 1 1/ A sample unit having one or more defects w
44、ill be considered as one defective. 2/ Marking will be considered as a defect only if it becomes illegible as a result of any of the tests. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-81F 7 4.3.2 Inspection routine table II. The sample sh
45、all be subjected to the inspections specified in , in the order shown. All sample units shall be subjected to the inspections of group I. The sample shall then be divided as specified in table II for group II and group III and subjected to the inspection for their particular group. 4.3.3 Failures ta
46、ble II. Failures in excess of those allowed in shall be cause for refusal to grant qualification. 4.4 Conformance inspection. 4.4.1 Inspection of product for delivery. Inspection of product for delivery shall consist of group A and group B inspection. 4.4.1.1 Inspection lot. An inspection lot shall
47、consist of capacitors of the same style and characteristic produced under essentially the same conditions, and offered for inspection at one time. 4.4.2 Group A inspection table III. Group A inspection shall consist of the examinations and tests specified in , in the order shown. 4.4.2.1 Sampling pl
48、an table III. The sampling plan shall be as specified in . TABLE III. Group A inspection. Inspection Requirement paragraph Method paragraph Sampling procedure Subgroup 1 Visual and mechanical inspection design, construction, and physical dimensions Marking Workmanship 3.1 and 3.4 3.18 3.20 to 3.20.2
49、 inclusive 4.6.1 13 samples 0 failures Subgroup 2 Dielectric withstanding voltage Insulation resistance Capacitance Dissipation factor 3.5 3.7 3.8 3.9 4.6.2 4.6.4 4.6.5 4.6.6 13 samples 0 failures 4.4.3 Group B inspection table IV. Group B inspection shall consist of the tests specified in , in the order shown. Shipment of capacitor lots shall not be accomplished until represe
