金卤灯电子镇流器技术

质量能保证2-3年包换,并且赔25US$吗?

设计寿命25000小时

继续忽油吧....................................

**此帖已被管理员删除**

哈哈.... 设计寿命.... 本人曾在3大照明公司工作过2家, 设计寿命是怎样计算出来的, 说来听听....

呵呵,又跑到这里卖元件了,,,,,,,,,,,,

五折???


赶紧清仓哦!!!!!

简直是乱弹琴,,什么是设计寿命?

不过用美国军事标准可靠性设计,也可以预估寿命

MILITARY HANDBOOK

RELIABILITY PREDICTION OF ELECTRONIC EQUIPMENT

1.1 Purpose - The purpose of this handbook is to establish and maintain consistent and uniform methods for estimating the inherent reliability (i.e., the reliability of a mature design) of military electronic equipment and systems. It provides a common basis for reliability predictions during acquisition programs for military electronic systems and equipment. It also establishes a common basis for comparing and evaluating reliability predictions of related or competitive designs. The handbook is intended to be used as a tool to increase the reliability of the equipment being designed.
1.2 Application - This handbook contains two methods of reliability prediction – “Part Stress Analysis" in Sections 5 through 23 and "Parts Count" in Appendix A. These methods vary in degree of information needed to apply them. The Part Stress Analysis Method requires a greater amount of detailed information and is applicable during the later design phase when actual hardware and circuits are being designed. The Parts Count Method requires less information, generally part quantities, quality level, and the application environment. This method is applicable during the early design phase and during proposal formulation. In general, the Parts Count Method will usually result in a more conservative estimate (i.e., higher failure rate) of system reliability than the Parts Stress Method.
1.3 Computerized Reliability Prediction-Rome Laboratory - ORACLE is a computer program developed to aid in applying the part stress analysis procedure of MIL-HD8K-217. Based on environmental use characteristics." piece part count, thermal and electrical stresses, subsystem repair rates and system configuration, the program calculates piece part, assembly and subassembly failure rates. It also flags overstressed parts, allows the user to .perform tradeoff analyses and provides system mean-time-to-failure and availability. The ORACLE computer program software (available in both VAX and IBM compatible PC versions) is available at replacement tape/disc cost to all DoD organizations, and to contractors for application on specific DoD contracts as government furnished property (GFP). A statement of terms and conditions may be obtained upon written request to: Rome Laboratory/ERSR. Griffins AFB. NY 13441-5700.


















                                                                                                
1-1.


MIL-HDBK-217F

2.0   REFERENCE DOCUMENTS                                                        

This handbook cites some specifications which have been cancelled or which describe devices that are not to be used for new design. This information is necessary because some of these devices are used in so-called "off-the-shelf" equipment which the Department of Defense purchases. The documents cited in this section are for guidance and Information.

SPECIFICATION SECTION# TITLE
MlL-C-5 10.7 Capacitors. Fixed. Mica-Dielectric. General Specification for
MIL-R-11 9.1 Resistor. Fixed, Composition (Insulated) General Specification for
MIL-R-19 9.11 Resistor, Variable. Wirewound (Low Operating Temperature) General Specification for
MIL-C-20 10.11 Capacitor, Fixed. Ceramic Dielectric (Temperature Compensating) Established and Nonestablished Reliability, General Specification for
MIL-R-22 9.12 Resistor, Wirewound. Power Type. General Specification for
MIL-C-25 10.1 Capacitor, Fixed, Paper-Dielectric. Direct Current (Hermetically Sealed in Metal Cases), General Specification for
MIL-R-26 9.6 Resistor. Fixed. Wirewound (Power Type), General Specification for
MIL-T-27 11.1 Transformer and Inductor (Audio, Power. High Power. High Power Pulse), General Specification for
MIL-C-62 10.15 Capacitor. Fixed Electrolytic (DC.Aluminum, Dry Electrolyte. Polarized), General Specification for
MIL-C-31 10.16 Capacitor. Variable. Ceramic Dielectric (Trimmer). General Specification for
MIL-C-92 10.18 Capacitor, Variable, Air Dielectric (Trimmer), General Specification for
MIL-R-93 9.5 Resistor, Fixed, Wirewound (Accurate), General Specification for
MIL-R-94 9.14 Resistor, Variable, Composition, General Specification for
MIL-V-95 23.1 Vibrator. Interrupter and Sett-Rectifying, General Specification for
W-L-111 20.1 Lamp. Incandescent Miniature. Tungsten Filament
W-C-375 14.5 Circuit Breaker, Molded Case. Branch Circuit and Service
W-F-1726 22.1 Fuse. Cartridge, Class H (This covers renewable and nonrenewable)
W-F-1814 22.1 Fuse, Cartridge, High Interrupting Capacity
MIL-C-3098 19.1 Crystal Unit, Quartz. General Specification for
MIL-C-3607 15.1 Connector, Coaxial, Radio Frequency, Series Pulse, GeneralSpecifications for
MIL-C-3643 15.1 Connector, Coaxial, Radio Frequency, Series NH, Associated Fittings. General Specification for
MIL-C-3650 15.1 Connector, Coaxial. Radio Frequency. Series'LC.












                                                                                                  
2-1
MIL-HDBK-217F

2.0 REFERENCE DOCUMENTS                                                                    




SPECIFICATION SECTION# TITLE
MIL-C-3855 15.1 Connector, Plug and Pecseteria. Electrical (Coaxial Series Twin) and Associated Fittings. General Specification for
MIL-C-3767 15.1 Connector, Plug and Receptacle (Power. Bladed Type) General Specification for
MlL-S-3786 14.3 Switch, Rotary (Circuit Selector, Low-Current (Capacity)). General Specification for
MlL-C-3950 14.1 Switch, Toggle. Environmentally Sealed, General Specification for
MIL-C-3965 10.13 Capacitor, Fixed. Electrolytic (Nonsolid Electrolyte). Tantalum. General Specification for
MIL-C-5015 15.1 Connector, Electrical, Circular Threaded, An Type, General Specification for
MIL-C-5372 22.1 Fuse, Current Limner Type, Aircraft
MIL-C-5757 13.1 Relay, Electrical(For Electronic and Communication Type Equipment.) General Specification for  
MIL-C-6106 13.1 Relay, Electromagnetic -(Including Established Reliability (ER) Types), General Specification for
MIL-L-6363 20.1 Lamp, Incandescent. Aviation Service, General Requirement for
MIL-S-8805 14.1,14.2 Switches and Switch Assemblies. Sensitive and Push. (Snap Action) General Specification for
MIL-S-8834 14.1 Switches, Toggle, Positive Break, General Specification for
MIL-M-10304 18.1 Meter, Electrical Indicating, Panel Type. Rugged zed, General Specification for
MIL-R-10509 9.2 Resistor, Fixed Film (High Stability). General Specification for
MIL-C-10950 10.8 Capacitor, Fixed, Mica Dielectric, Button Style, General Specification for
MIL-C-11015 10.10 Capacitor. Fixed, Ceramic Dielectric (General Purpose). General Specification for
MIL-C-11272 10.9 Capacitor, Fixed, Glass Dielectric, Genera! Specification for
MIL-C-11693 10.2 Capacitor, Feed Through, Radio Interference Reduction AC and DC, (Hermetically Sealed in Metal Cases) Established and Nonestablished Reliability. General Specification for
MIL-R-11804 9.3 Resistor, Fixed. Film (Power Type). General Specification for
MIL-C-12889 10.1 Capacitor, By-Pass, Radio - Interference Reduction, Paper Dielectric, AC and DC, (Hermetically Sealed in Metallic Cases). General Specification for
MIL-R-12934 9.10 Resistor, Variable, Wirewound, Precision, General Specification for




                                                                                                  
2-2

MIL-HDBK-217F

2.0 REFERENCE DOCUMENTS                                                                      

SPECIFICATION SECTION# TITLE
MIL-C-14157 10.3 Capacitor, Fixed. Paper (Paper Plastic) or Plastic Dielectric, Direct Current (Hermetically Sealed in Metal Cases) Established Reliability. General Specification for
MIL-C-14409 10.17 Capacitor. Variable (Piston Type, Tubular Trimmer). General Specification for
MIL-F-15160 22.1 Fuse. Instrument, Power and Telephone
MIL-C-15305 11.2 Coil. Fixed and Variable. Radio Frequency. General Specification for
MIL-F-15733 21.1 Filter. Radio Interference. General Specification for
MIL-C-18312 10.4 Capacitor. Fixed. Moralized (Paper. Paper Plastic or Plastic Rim) Dielectric. Direct Current (Hermetically Sealed in Metal Cases). General Specification for
MIL-F-18327 21.1 Filter. High Pass. Low Pass. Band Pass. Band Suppression and Dual Functioning. General Specification for
MIL-R-18546 9.7 Resistor. Fixed. Wirewound (Power Type, Chassis Mounted), General Specification for
MIL-S-19500 6.0 Semiconductor Device. General Specification for
MIL-R-19523 13.1 Relay. Control. Naval Shipboard
MIL-R-19648 13.1 Relay. Time, Delay, Thermal. General Specification for
MIL-C-19978 10.3 Capacitor. Fixed Plastic (or Paper-Plastic) Dielectric (Hermetically Sealed in Metal, Ceramic or Glass Cases). Established and Nonestablished Reliability, General Specification for
MIL-T-21038 11.1 Transformer, Pulse, Low Power, General Specification for
MIL-C-21097 15.2 Connector, Electrical, Printed Wiring Board. General Purpose. General Specification for
MIL-R-22097 9.13 Resistor, Variable, Nonwirewound (Adjustment Types), General Specification for
MIL-R-22684 9.2 Resistor. Fixed, Film, Insulated, General Specification for
MIL-S-22710 14.4 Switch. Rotary (Printed Circuit), (Thumbwheel, In-line and Pushbutton). General Specification for
MIL-S-22885 14.1 Switches, Pushbutton. Illuminated. General Specification for
MIL-C-22992 15.1 Connector, Cylindrical, Heavy Duty, General Specification for
MIL-C-23183 10.19 Capacitor, Fixed or Variable, Vacuum Dielectric, General Specification for
MIL-C-23269 10.9 Capacitor, Fixed, Glass Dielectric, Established Reliability. General Specification for
MIL-R-23285 9.15 Resistor, Variable, Nonwirewound, General Specification for







                                                                                                
2-3

SPECIFICATION SECTION # TITLE
MIL-F-23419 22.1 Fuse. Instrument Type, General Specification for
MIL-T-23648 9.8 Thermostat. (Thermally Sensitive Resistor). Insulated. General Specification for
MIL-C-24308 15.1 Connector. Electric, Rectangular. Miniature Polarized Shell. Rack and Panel. General Specification for
MIL-C-25516 15.1 Connector. Electrical, Miniature, Coaxial, Environment Resistant Type. General Specification for
MlL-C-26482 15.1 Connector. Electrical (Circular, Miniature, Quick Disconnect, Environment Resisting) Receptacles and Plugs. General Specification for
MIL-R-27208 9.9 Resistor, Variable. Wirewound, (Lead Screw Activated) General ... Specification for
MIL-C-28748 15.1 Connector. Electrical, Rectangular. Rack and Panel, Solder Type and Crimp Type Contacts, General Specification for
MIL-R-29750 13.1 Relay. Solid State. General Scarification for
MIL-C-28804 15.1 Connector, Electric Rectangular. High Density. Polarized Central Jackscrew, General Specification for. Inactive for New Designs
MlL-C-28840 15.1 Connector. Electrical. Circular Threaded, High Density, High Shock Shipboard, Class D, General Specification for
MIL-M-38510 5.0 Micrococcus, General Specification for
MlL-H-38534 5.0 Hybrid Micrococcus, General Specification for
MIL-l-38535 5.0 Integrated Circuits (Micrococcus) Manufacturing. General Specification for
MIL-C-38999 15.1 Connector, Electrical, Circular, Miniature, High Density, Quick Disconnect, (Bayonet, Threaded, and Breech Coupling) Environment Resistant. Removable Crimp and Hermetic Solder Contacts, General Specification for.
MIL-C-39001 10.7 Capacitor, Fixed, Mica Dielectric, Established Reliability, General Specification for
MIL-R-39002 9.11 Resistor. Variable, Wirewound, Semi-Precisian, General Specification for
MIL-C-39003 10.12 Capacitor, Fixed, BectroJytic. (Solid Electrolyte). Tantalum, Established Reliability, General Specification for
MIL-R-39005 9.5 Resistor. Faed, Wirewound, (Accurate) Estabfished Refiabflrty. General Specification for
MIL-C-39006 10.13 Capacitor, Fixed, Electrolytic (Nonsolid Electrolyte) Tantalum Established Reliability, General Specification for
MIL-R-39007 9.6 Resistor, Faed. Wirewound (Power Type) Established Reliability. General Specification for




                                                                                              
2-4



MIL-HDBK-217F
2,0  REFERENCE    DOCUMENTS                                                            

SPECIFICATION SECTION# TITLE
MIL-R-39008 9.1 Resistor, Fixed, Composition. (Insulated) Established Reliability. General Specification for
MIL-R-39009 9.7 Resistor. Fixed. Wirewound (Power Type. Chassis Mounted) Established Reliability. General Specification for
MIL-C-39010 11.2 Coil, Fixed. Radio Frequency. Molded. Established Reliability. General Specification for pangs
MIL-C-39012 15.1 Connector, Coaxial. Radio Frequency. General Specification for
MIL-C-39014 10.10 Capacitor. Fixed. Ceramic Dielectric (General Purpose) Established Reliability, General Specification for
MIL-C-39015 9.9 Resistor, Variable. Wirewound (Lead Screw Actuated) Established Reliability. General Specification for
MlL-R-39016 13.1 Relay, Electromagnetic. Established Reliability. General Specification for
MlL-R-39017 9.2 Resistor Fixed, Film (Insulated), Established Reliability, General Specification for
MIL-C-39018 10.14 Capacitor, Fixed, Electrolytic (Aluminum Oxide) Established Reliability and Nonestablished Reliability. General Specification for
MIL-C-39019 14.5 Circuit Breakers, Magnetic, Low Power. Sealed. Trip-Free, General Specification for
MIL-C-39022 10.4 Capacitor. Fixed. Metallized Paper, Paper-Plastic Flm. or Plastic Film Dielectric. Direct and Alternating Current (Hermetically Sealed in Metal Cases) Established Reliability. General Specification for
MIL-R-39023 9.15 Resistor, Variable, Nonwirewound, Precision, General Specification for
MIL-R-39035 9.13 Resistor. Variable. Nonwirewound. (Adjustment Type) Established Reliability, General Specification for
MIL-C-49142 15.1 Connector, Triaxial, RF. General Specification for
MIL-P-55110 15.2 Printed Wiring Boards
MIL-R-55182 9.2 Resistor. Fixed. Film, Established Reliability, General Specification for
MIL-C-55235 15.1 Connector, Coaxial, RF, General Specification for
MIL-C-55302 15.2 Connector, Printed Circuit, Subassembly and Accessories
MlL-C-55339 15.1 Adapter, Coaxial, RF. General Specification for
MIL-C-55514 10.5 Capacitor. Fixed, Plastic (or Metallized Plastic) Dielectric, Direct Current, In Non-Metal Cases, General Specificalion for
MlL-C-55629 14.5 Circuit Breaker, Magnetic, Unsealed, Trip-Free, General Specification for
MIL-T-55631 11.1 Transformer, Intermediate Frequency. Radio Frequency, and Discriminator. General Specification for





                                                                                            
2-5
MIL-HDBK-217F
2.0 REFERENCE DOCUMENTS                                                                  

SPECIFICATION SECTION# TITLE
MIL-C-33881 10.11 Capacitor, Chip, Miniature Layer Fixed,Ceramic Dielectric, Estabisnad Reliability General Specification for
MIL-C-81511 15.1 Connector, Electrical, Circular, High Density, Quick Disconnect, Environment Resisting, and Accessories, General Specification for
MIL-C-83383 14.5 Circuit Breaker, Remote Control, Thermal, Trip-Free, General Specification For
MIL-R-83401 9.4 Resistor Networks, Fixed, Film, General Specification for
MIL-C-83421 10.6 Capacitor, Fixed Supermetallized Plastic Film Dielectric (DC, AC or DC and AC) Hermetically Sealed in Metal Cases, Established Reliability, General Specification for
MIL-C-83513 15.1 Connector, Electrical, Rectangular, Microminiature, Polarized Shell, General Specification for
MIL-C-83723 15.1 Connector, Electrical (Circular Environment Resisting). Receptacles and Plugs, General Specification for
MIL-P-83725 13.1 Relay, Vacuum, General Specification for
MIL-R-83726 13.1,13.2,13.3 Relay, Time Delay, Electric and Electronic, General Specification for
MIL-S-83731 14.1 Switch, Toggle, Unsealed and Sealed Toggle, General Specification for
MIL-C-83733 15.1 Connector, Electrical, Miniature, Rectangular Type, Rack to Panel, Environment Resisting, 200 Degrees C Total Continuous Operating Temperature, General Specification for
MIL-S-83734 15.3 Socket, Plug-in Electronic

STANDARD TITLE
MIL-STD-756 Reliability Modeling and Prediction
MIL-STD-883 Test Methods and Procedures for Microelectronics
MIL-STD-975 NASA Standard Electrical, Electronic and Electromechanical Parts List
MIL-STD-1547 Parts, Materials and Processes for Space Launch Vehicles, Technical Requirements for
MIL-STD-1772 Certification Requirements for Hybrid Microcircuit Facilities and Lines

Copies of specifications and standards required by contractors in connection with specific acquisition functions should be obtained from the contracting activity or as directed by the contracting officer. Single copies are also available (without charge) upon written request to:
















                                                                                            
2-6
MIL-HDBK-217F
3.0 INTRODUCTION                                                                          
3.1 Reliability Engineering - Reliability is currently recognized as an essential need in military electronic systems. It is looked upon as a means for reducing costs from the factory, where rework of defective components adds a non-productive overhead expense, to the field, where repair costs include not only parts and labor but also transportation and storage. More importantly, reliability directly impacts force effectiveness, measured in terms of availability or sortie rates, and determines the size of the "logistics tail" inhibiting force utilization.
The achievement of reliability is the function of reliability engineering. Every aspect of an electronic system, from the purity of materials used in its component devices to. the operators interface, has an impact on reliability. Reliability engineering must, therefore, be applied throughout the system's development in a diligent and timely fashion; and integrated with other engineering disciplines.
A variety of reliability engineering tools have been developed. This handbook provides the models supporting a basic tool, reliability prediction.
3.2 The Role of Reliability Prediction-Reliability prediction provides the quantitative baseline
needed to assess progress in reliability engineering. A prediction made of a proposed design may be
used in several ways.
A characteristic of Computer Aided Design is the ability to rapidly generate alternative solutions to a particular problem. Reliability predictions for each design alternative provide one measure of relative worth which, combined with other considerations, will aid in selecting the best of the available options.
Once a design is selected, the reliability prediction may be used as a guide to improvement by showing the highest contributors to failure. If the part stress analysis method is used, it may also reveal other fruitful areas for change (e.g., over stressed parts).
The impact of proposed design changes on reliability can be determined only by comparing the reliability predictions of the existing and proposed designs.
The ability of the design to maintain an acceptable reliability level under environmental extremes may be assessed through reliability predictions. The predictions may be used to evaluate the need for environmental control systems.
The effects of complexity on the probability of mission success can be evaluated through reliability predictions. The need for redundant or back-up systems may be determined with the aid of reliability predictions. A tradeoff of redundancy against other reliability enhancing techniques (e.g.: more cooling, higher part quality, etc.) must be based on reliability predictions coupled with other pertinent considerations such as cost, space limitations, etc.
The prediction will also help evaluate the significance of reported failures. For example, if several failures of one type or component occur in a system, the predicted failure rate can be used to determine whether the number of failures is commensurate with the number of components used in the system, or, that it indicates a problem area.
Finally, reliability predictions are useful to various other engineering analyses. As examples, the location of buflt-in-test circuitry should be influenced by the predicted failure rates of the circuitry monitored, and maintenance strategy planners can make use of the relative probability of a failure's location, based on predictions, to minimize downtime. Reliability predictions are also used to evaluate the probabilities of failure events described in a failure modes, effects and crrtical'rty analysis (FMECAs).




                                                                                            
3-1

MIL-HDBK-217F

3.0  INTRODUCTION                                                                    

3.3 Limitations of Reliability Predictions - This handbook provides a common basis for reliability predictions, based on analysis of the best available data at the time of issue. It is intended to make reliability prediction as good a tool as possible. However, like any tool, reliability prediction must be usecf Jni-silsgertJy, with due consideration of its limitations.

The first limitation is that the failure rate models are point estimates which are based on available data. Hence, they are valid for the conditions under which the data was obtained, and for the devices covered. Some extrapolation during model development is possible, but the inherently empirical nature of the models can be severely restrictive. For example, none of the models in this handbook predict nuclear survivabflity or the effects of ionizing radiation.

Even when used in similar environments, the differences between system applications can be significant. Predicted and achieved reliability have always been doser for ground electronic systems than for avionic systems, because the environmental stresses vary less from system to system on the ground and hence the field conditions are in general closer to the environment under which the data was collected for the prediction model. However, failure rates are also impacted by operational scenarios, operator characteristics, maintenance practices, measurement techniques and differences in definition of failure. Hence, a reliability prediction should never be assumed to represent the expected field reliability as measured by the user (i.e., Mean-Time-Between-Maintenance, Mean-Time-Between-Removals, etc.). This does not negate its value as a reliability engineering tool; note that none of the applications discussed above requires the predicted reliability to match the field measurement.

Electronic technology is noted for its dynamic nature. New types of devices and new processes ars co;n;nuaiiy introduced, compounding me difficulties of precic.;ng reiiacilfty. Evolutionary changes may oe handled by extrapolation from the existing models; revolutionary changes may defy analysis.

Another limitation of reliability predictions is the mechanics of the process. The part stress analysis method requires a significant amount of design detail. This naturally imposes a time and cost penatty. More significantry, many of the details are not available in the early design stages. For this reason this handbook contains both the part stress analysis method (Sections 5 through 23) and a simpler parts count method (Appendix A) which can be used In early design and bid formulation stages.

Finalty, a basic-limitation of reliability prediction is its dependence on correct application by the user. Those who correctly apply the models and use the information in a conscientious reliability program will find the prediction a useful tool. Those who view the prediction onfy as a number which must exceed a specified value can usually find a way to achieve their goal without any impact on the system.

3.4  Part Stress Analysis Prediction
3.4.1 Applicability - This method is applicable when most of the design is completed and a detailed parts list including part stresses Is available. It can also be used during later design phases for reliability trade-offs vs. part selection and stresses. Sections 5 through 23 contain failure rate models for a broad variety of parts used in electronic equipment. The parts are grouped by major categories and, where appropriate, are subgrouped within categories. For mechanical and electro mechanical parts not covered by this Handbook, refer to Bibliography items 20 and 36 (Appendix C).
The failure rates presented apply to equipment under normal operating conditions, i.e., with power on and performing its intended functions in its intended environment Extrapolation of any of the base failure rate models beyond the tabulated values such as high or sub-zero temperature, electrical stress values above 1.0, or extrapolation of any associated model modifiers is completely invalid. Base failure rates can be interpolated between electrical stress values from 0 to 1 using the underlying equations.
The general procedure for determining a board level (or system level) failure rate is to sum individually calculated failure rates for each component. This summation is then added to a failure rate for the circuit board (which includes the effects of soldering parts to it) using Section 16, Interconnection Assemblies

                                                                                              
3-2



MIL-HDBK-217F
3.0  INTRODUCTION                                                                  
For parts or wires soldered together (e.g., a jumper wire between two parts), the connections model appearing in Section 17 is used. Finally, the effect of connecting circuit boards together is accounted for by adding in a failure rate for each connector (Section 15, Connectors). The wire between connectors is assumed to have a zero failure rate. For various service use profiles, duty cycles and redundancies the procedures described in MIL-STD-756, Reliability Modeling and Prediction, should be used to determine an effective system level failure rate.
3.4.2 Part Quality - The quality of a part has a direct effect on the part failure rate and appears in the part models as a factor, πq. Many parts are covered by specifications that have several quality levels, hence, the part models have values of πq  that are keyed to these quality levels. Such parts with their quality designators are shown in Table 3-1. The detailed requirements tor these levels are clearly defined in the applicable specification, except for microcircuits. Microcircuits have quality levels which are dependent on the number of MIL-STD-883 screens (or equivalent) to which they are subjected.

Table 3-1:   Parts With Multi-Level Quality Specifications

Part Quality Designators
Microcircuits S, B, B-1, Other: Quality Judged by Screening Level
Discrete Semiconductors JANTXV, JANTX, JAN
Capacitors, Established Reliability(ER) D, C, S, R, B, P, M, L
Resistors, Established Reliability(ER) S, R, P, M
Coils, Molded, R.F., Reliability(ER) S, R, P, M
Relays, EstabishedRelisbility(ER) R, P, M, L


Some parts are covered by older specifications, usually referred to as Nonestablished Reliability (Non-ER), that do not have multi-levels of quality. These part models generally have two quality levels designated as "MIL-SPEC.", and "Lower". If the part is procured in complete accordance with the applicable specification, the kq value for MIL-SPEC should be used. If any requirements are waived, or if acommercial part is procured, the kq value for Lower should be used.
The foregoing discussion involves the "as procured" part quality. Poor equipment design, production, and testing facilities can degrade part quality. The use of the higher quality parts requires a total equipment design and quality control process commensurate wrth the high part quality. It would make little sense to procure high quality parts only to have the equipment production procedures damage the parts or introduce latent defects. Total equipment program descriptions as they might vary with different part quality mixes is beyond the scope of this Handbook. Reliability management and quality control Procedures are described in other DoD standards and publications. Nevertheless, when a proposed equipment development is pushing the state-of-the-art and has a high reliability requirement necessitating high quality parts, the loiai equipment program should be given careful scrutiny and not just




                                                                                            
3-3

MIL-HDBK-217F
3.0  INTRODUCTION                                                        
the carts quality. Otherwise, the low failure rates as predicted by the models for high quality parts will not be realized.
3.4.3 Use Environment - All part reliability models include the effects of environmental stresses through the environmental factor, πE,  except for the effects of ionizing radiation. The descriptions of these environments are shown in Table 3-2. The πE factor is quantified within each part failure rate model. These environments encompass the major areas of equipment use. Some equipment will experience more than one environment during its normal use, e.g., equipment in spacecraft. In such a case, the reliability analysis should be segmented, namely, missile launch (ML) conditions during boost into and return from orbit, and space flight (SF) while in orbit.
Table 3-2:    Environmental Symbol and Description

Environment πE Symbol Equivalent MIL-HDBK-217E, Notice 1 πE Symbol Description
Ground, Benign GB GBGMS No mobile, temperature and humidity controlled environments readily accessible to maintenance: includes laboratory instruments and test equipment, medical electronic equipment, business and scientific computer complexes, and missiles and support equipment in ground silos.
Ground, Fised GF GF Moderately controlled environments such as installation in permanent racks with adequate cooling air and possible installation in unheated buildings: includes Pennanent installation of air traffic control radar and communications facilities.
Ground, Mobile GM GMMP Equipment installed on wheeled or tracked vehicles and epuipment manually transported: includes tactical missile ground support equipment, mobile communication equipment, tactical fire direction systems, handheld communications equipment, laser designations and range finders.
Naval, Sheltered Ns NSNSB Includes sheltered or below deck conditions on surface ships and equipment installed in submarines.
Naval, Unsheltered NU NUNUUNH Unprotected surface shipbome equipment exposed to weather conditions and equipment immersed in salt water, Includes sonar Equipment and equipment installed on hydrofoil vessels.








3-4

MIL-HDBK-217F


3.0  INTRODUCTION                                                                  

Table 3-2:    Environmental Symbol and Description (cont'd)

Environment πE Symbol Equivalent MIL-HDBK-217ENotice 1πE Symbol Description
Airborne, Inhabited, Cargo AIC AICAITAIB Typical conditions in cargo compartments which can be occupied by an aircrew. Environment extremes of pressure, temperature, shock and vibration are minimal. Examples include long mission aircraft such as the C130. C5, BS2, and C141. This category also applies to inhabited areas in lower performance smaller aircraft such as the T38
Airbome, Inhabited, Fighter AIF AIFAIA Same as ajq but installed on high performanceaircraft such as fighters and interceptors. Examples include the F15. F16. F111, F/A 18 and A10 aircraft.
Airbome, Uninhabited, Cargo AUC AUCAUTAUB Environmentally uncontrolled areas which cannot be inhabited by an aircrew during flight. Environmental extremes of pressure, temperature and shock may be severe. Examples indude uninhabited areas of long mission aircraft such as the C130. C5, 852 and C141. This category also applies to uninhabited area of lower performance smaller aircraft such as the T38.
Airborne, Uninhabited, Fighter AUF AUFAUA Same as AyQ but installed on high performanceaircraft such as fighters and interceptors. Examples indude the F15,F16, F111 and A10 aircraft
Airborne, Rotary Winged ARW ARW Equipment installed on helicopters. Applies to both internally and externally mounted equipment such as laser designators, fire control systems, and communications equipment.
Space, Flight SF SF Earth orbital. Approaches benign ground conditions. Vehicle neither under powered flight nor in atmospheric reentry; indudes satellites and shuttles.








                                                                                            
3-5


MIL-HDBK-217F

3.0  INTRODUCTION                                                                



Table 3-2:    Environmental Symbol and Description (cont'd)

Environment πE  Symbol Equivalent MIL-HDBK-217E, Notice 1πE  Symbol Description
Missile, Flight MF MFFMFA Conditions related to powered flight of air breathing missiles, cruise missiles, and missiles in unpowered free flight.
Missile, Launch ML MLUSL Severe conditions related to missile launch (air. ground and sea), space vehicle boost into orbit, and vehicle re-entry and landing by parachute. Also applies to solid rocket motor propulsion powered flight, and torpedo and missile launch from submarines.
Cannon, Launch CL CL Extremely severe conditions related to cannon launching of 155mm. and 5 inch guided projectiles. Conditions apply to the projectile from cannon to target impact.


3.4.4 Part Failure Rate Models - Part failure rate models for microelectronic parts are significantly different from those for other parts and are presented entirely in Section 5.0. A typical example of the type of model used for most other part types is the following one for discrete semiconductors:




where:
  is the part failure rate,

       is the base failure rate usually expressed by a model relating the influence of electrical and temperature stresses on the part,
  and the other jc factors modify the base failure rate for the category of environmental sppScation and other parameters that affect the part reliability.

TheπE andπq factors are used In most all models and otherπfactors apply only to specific models. The applicability ofπfactors Is Identified in each section.
The base failure rate (λb) models are presented in each part section along with identification of the applicable model factors. Tables of calculatedλb values are also provided for use in manual calculations.
The model equations can, of course, be incorporated into computer programs for machine processing. The tabulated values ofλb are cut off at the part ratings with regard to temperature and stress, hence, use
of parts beyond these cut off points will overstress the part.  The use of theλb, models in a computer

                                                                                          
3-6

MIL-HDBK-217F
3.0  INTRODUCTION                                                          

Program should take the part rating limits into account. The λb equations are mathematically continuous beyond the part ratings but such failure rate values are invalid in the overstressed regions.
All the part models include failure data from both catastrophic and permanent drift failures (e.g., a resistor permanently falling out of rated tolerance bounds) and are based upon a constant failure rate, except for motors which show an increasing failure rate over time. Failures associated with connection of parts into circuit assemblies are not included within the part failure rate models. Information on connection reliability is provided in Sections 16 and 17.
3.4.5 Thermal Aspects - The use of this prediction method requires the determination of the temperatures to which the parts are subjected. Since parts reliability is sensitive to temperature, the thermal analysis of any design should fairly accurately provide the ambient temperatures needed in using the part models. Of course, lower temperatures produce better reliability but also can produce increased penalties in terms of added loads on the environmental control system, unless achieved through improved thermal design of the equipment. The thermal analysis should be part of the design process and included in all the trade-off studies covering equipment performance, reliability, weight, volume, environmental control systems, etc. References 17 and 34 fisted in Appendix C may be used as guides in determining component temperatures.






















                                                                                            
3-7


MIL-HDBK-217F

4.0  RELIABILITY ANALYSIS  EVALUATION                                          


Table 4-1 provides a general checklist to be used as a guide for evaluating a reliability prediction report. For completeness, the checklist includes categories for reliability modeling and allocation, which are sometimes delivered as part of a prediction report. It should be noted that the scope of any reliability analysis depends on the specific requirements called out in a statement-of-work (SOW) or system specification. The inclusion of this checklist is not intended to change the scope of these requirements.

Table   4-1:     Reliability   Analysis  Checklist
Major   Concerns Comments

MODELS
Are ail functional elements included in the reliability block diagram /model? System design drawings/diagrams must be reviewed to be sure that the reliability model/diagram agrees with the hardware.
Are all modes of operation considered in the math model? Duty cycles, alternate paths, degraded conditions and redundant units must be defined and modeled.
Do the math model results show that the design achieves the reliability requirement? Unit failure rates and redundancy equations are used from the detailed part predictions in the system math model (See MIL-STD-756, Reliability Prediction and Modeling).

ALLOCATION
Are system reliability requirements allocated (subdivided) to useful levels? Useful levels are defined as: equipment for subcontractors, assemblies for sub-subcontractors, circuit boards for designers.
Does the allocation process consider complexity, design flexibility, and safety margins? Conservative values are needed to prevent reallocation at every design change.

PREDICTION
Does the sum of the parts equal the value of the module or unit? Many predictions neglect to include all the parts producing optimistic results (check for solder connections; connectors, circuit boards).
Are environmental conditions and part quality representative of the requirements? Optimistic quality levels and favorable environmental conditions are often assumed causing optimistic results.
Are the circuit and part temperatures defined and do they represent the design? Temperature is the biggest driver of part failure rates; tow temperature assumptions will cause optimistic results.
Are equipment, assembly, subassembly and part reliability drivers identified? identification is needed so that corrective actions for reliability improvement can be considered.
Are alternate (Non MIL-HDBK-217) failure rates highlighted along with the rational* for their use? Use of alternate failure rates, if deemed necessary, require submission of backup data to provide credence in the values.
Is the level of detail for the part failure rate models sufficient to reconstruct the result? Each component type should be sampled and failure rates completely reconstructed for accuracy.
Are critical components such as VHSIC, Monolithic Microwave Integrated Circuits (MMlC). Application Specific Integrated Circuits (ASIC) or Hybrids highlighted? Prediction methods for advanced technology parts should be carefully evaluated for impact on the module and system.






                                                                                                  
4-1
MIL-HDBK-217F

5.0     MICROCIRCUITS,   INTRODUCTION                                                      


This section presents failure rate prediction models for the following ten major classes of microelectronic devices:

Section

5.1   Monolithic Bipolar Digital and Linear Gate/Logic Array Devices

5.1   Monolithic MOS Digital and Linear Gate/Logic Array Devices

5.1   Monolithic Bipolar and MOS Digital Microprocessor Devices

5.2   Monolithic Bipolar and MOS Memory Devices

5.3   Very High Speed Integrated Circuit (VHSlC/VHSlC-Like and VLSI) CMOS Devices (> 60K Gates)

5.4   Monolithic GaAs Digital Devices

5.4   Monolithic GaAs MMIC

5.5   Hybrid Microcircuits
          
5.6   Surface Acoustic Wave Devices

5.7   Magnetic Bubble Memories


In the title description of each monolithic device type. Bipolar represents all TTL, ASTTL. DTL, ECL, CML,ALSTTL. HTTL, FTTL. F. LTTL. STTL, BICMOS, LSTTL. IIL, I3L and ISL devices. MOS represents all metal-oxide microcircuits, which includes NMOS, PMOS, CMOS and MNOS fabricated on various substrates such as sapphire, polycrystalline or single crystal silicon. The hybrid model is structured to accommodate all of the monolithic chip device types and various complexity levels.

Monolithic memory complexity factors are expressed in the number of bits in accordance with JEDEC STD 21 A. This standard, which is used by all government and industry agencies that deal with microcircuit memories, states that memories of 1024 bits and greater shall be expressed as K bits, where 1K = 1024 bits. For example, a 16K memory has 16.384 bits, a 64K memory has 65,536 bits and a 1M memory has 1,048,576 bits. Exact numbers of bits are not used for memories of 1024 bits and greater.

For devices having both linear and digital functions not covered by MIL-M-38510 or MlL-l-38535, use the linear model. Line drivers and line receivers are considered linear devices. For linear devices not covered by MIL-M-38510 or MIL-l-38535, use the transistor count from the schematic diagram of the device to determine circuit complexity.

For digital devices not covered by MlL-M-38510 or MIL-1-38535, use the gate count as determined from the logic diagram. A J-K or R-S flip flop is equivalent to 6 gates when used as part of an LSI circuit. For the Purpose of this Handbook, a gate is considered to be any one of the following functions; AND, OR, exclusive OR, NAND, NOR and inverter. When a logic diagram is unavailable, use device transistor count to determine gate count using the following expressions:

Technology Gate Approximation
Bipolar No. Gates = No, Transistors/3.0
CMOS No. Gates = No. Transistors/4.0
All other MOS except CMOS No. Gates = No. Transistors/3.0


                                                                                              
5-1

MIL-HDBK-217F

5.0      MICROCIRCUITS,   INTRODUCTION                                                  


A detailed form of the Section 5.3 VHSIC/VHSIC-Like model is included as Appendix B to allow m     detailed trade-offs to be performed. Reference 30 should be consulted for more information abo:,
model.

Reference 32 should be consulted for more information about the models appearing in Sections 5.1, 5.3, 5.4, 5.5, and 5.6. Reference 13 should be consulted for additional information on Section 5.7.

DESCRIPTION1. Bipolar Devices, Digital and Linear Gate/Logic Arrays2. MOS Devices, Digital and Linear Gate/Logic Arrays3. Field Programmable Logic Array (PLA) and Programmable Array Logic (PAL)4. Microprocessors


Failures/106 Hours


Bipolar Digital and Linear Gate/Logic Array Die Complexity Failure Rate - C1
Digital Linear PLA/PAL
No. Gates C1 No. Transistors C1 No. Gates C1

1 to 100 .0025 1 to 100 .010 Up to 200 .010
101 to 1,000 .0050 101 to 300 .020 201 to 1,000 .021
1,001 to 3,000 .010 301 to 1,000 .040 1,001 to 5,000 .042
3,001 to 10,000 .020.040 1,001 to 10,000 .060
10,001 to 30,000 .040
30,001 to 60,000 .080




MQS Digital and Unear Gate/Logic Array Die Complexity Failure Rate –C1
Digital Linear PLA/PAL
No. Gates C1 No. Transistors C1 No. Gates C1

1 to 100 .010 1 to 100 .010 Up to 500 .00085
101 to 1,000 .020 101 to 300 .020 501 to 1,000 .0017
1,001 to 3,000 .040 301 to 1,000 .040 2,001 to 5,000 .0034
3,001 to 10,000 .080.040 1,001 to 10,000 .060 5,001 to 20,000 .0068
10,001 to 30,000 .16
30,001 to 60,000 .29


．NOTE: For CMOS gate counts above 60,000 use the VHSIC/VHSIC-Like model in Section 5.3


Microprocessor                                      
Die Complexity Failure Rate - C1                            All Other Model Parameters
No. Bits Bipolar MOS Parameter Refer to
Cl C1 πT Section 5.8
Up to 8 .060 .14 C2 Section 5.9
Up to 1 6 .12 .28 πE, πQ, πL Section 5.10
Up to 32 .24 .56




                                                                                                
5-3


MIL-HDBK-217F


5.2  MICROCIRCUITS, MEMORIES











  Failures/106 Hours

Die Complexity Failure Rate – C1
MOS Bipolar
Memory Size. B (Bits) ROM PROM,UVEPROM.EEPROM. EAPFIOM DRAM SRAM(MOS'SBiMOS) ROM,PROM SRAM
Up to 16K .00065 .00085 .0013 .0078 .0094 .0052
5K64K256K

A1 Factor forλcyc Calculation
Total No. ofProgrammingCycles Over EEPROM Life, C Flotox1 Textured-Poly2
Up to 100 .00070 .0097
100 200 < C≤500 .0034 .023
5001K3K7K15K20K30K100K200K400K1. A1 =6.817x10-6(C)2. No underlying equation for Textured Poly.


Factor forλcyc Calculation
Total No. of Programming Cycles Over EEPROM Life.C Texlured-Poly A2
Up to 300K 300K < C ≤ 400K400K < C≤ 500K 01.12.3

All Other Model Parameters
Parameter Refer to
πT Section 5.8
C2 Section 5.9
πe, πq, πL Section 5.10
λcyc (EEPROMS only) Page 5-5
λcyc = 0  For all other devices








                                                                                                  

5-4

MIL-HDBK-217F

5.2  MICROC1RCU1TS, MEMORIES                                                                


EEPROM Read/Write Cycling Induced Failure Rate –λcyc

All Memory Devices Except Flotox and Textured-Poly EEPROMS λcyc=0
Flotox and Textured Poly EEPROMS λcyc= πECC

Model Factor Flotox Textured-Poly
A1 Page 5-4 Page 5-4
B1 Page 5-6 Page 5-6
A2 A2=0 Page 5-5
B2 B2=0 Page 5-6
πQ Section 5.10 Section 5.10

Error Correction Code (ECC) Options:
   1. No On-Chip ECC πECC=1.0 πECC=1.0
   2. On-Chip Hamming Code πECC=.72 πECC=.72
   3. Two-Needs-One πECC=.68 πECC=.68
     Redundant Cell Approach

NOTES: 1. See Reference 24 for modeling off-chip error detection and correction schemes at the
memory system level.

2. If EEPROM type is unknown, assume Fbtox.

3. Error Correction Code Options: Some EEPROM manufacturers have incorporated
on-chip error correction circuitry into their EEPROM devices. This is represented by the
on-chip hamming code entry. Other manufacturers have taken a redundant cell
approach which incorporates an extra storage transistor in every memory cell. This is
represented by the two-needs-one redundant cell entry.

4. The A1 and A2 factors shown in Section 5.2 were developed based on an assumed
system life of 10,000 operating hours. For EEPROMs used In systems with significantly
longer or shorter expected fif etlmes the A1 and A2 factors should be multiplied by:














                                                                                    
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MIL-HDBK-217F

Page ; 028


IE O CD X IV)


MIL-HDBK-217F

5.3 MICROCIRCUITS, VHSIC/VHSIC-LIKE AND VLSI CMOS                              

DESCRIPTION
CMOS greater than 60,000 gates


λp=λBDπMFGπTπCD +λBPπEπQπPTλEOS Failures /106Hours

Die Base Failure Rate-λBD All Other Model Parameters
Part Type λBD Parameter Refer to
Logic and Custom 0.16 πT Section 5.8
Gate Array 0.24 πE.πQ Section 5.10

Package Type Correction Factor-πPT
Manufacturing Process Correction Factor-πMFG Package Type πPT
Manufacturing Process πMFG Hermetic Nonhermetic
QML or QPL .55 DIP 1.0 1.3
Non QML or Non QPL 2.0 Pin Grid Array 2.2 2.9
Chip Carrier 4.7 6.1
(Surface Mount
Technology)


Die Complexity Correction Factor –πCD
Feature Size(Microns) Die Area (cm2)
A ≤A .4 < A≤7 .7 < A≤1.0 1.0 .80 8.0 14 19 38 58
1.00 5.2 8.9 13 25 37
1.25 3.5 5.8 8.2 16 24
πCD =      A=Total Scribed Chip Die Area in cm2    XS=Feature Xize (mierons)
Die Area Conversion:cm2 = MIL2 / 155,000



Package Base Failure Rate-λBP Electrical Overstress Failure Rate-λEOS
Number of Pins λBP VTH(ESD Susceptibility (Volts)) λEOS
24 .0026
28 .0027 0-1000 .065
40 .0029
44 .0030 >1000-2000 .053
48 .0030
52 .0031 >2000-4000 .044
64 .0033
84 .0036 >4000-16000 .029
120 .0043
124 .0043 >16000 .0027
144 .0047 λEOS=(-In(1-.00057 exp(-.0002 VTH)) /.00876
220 .0060 VTH =ESD Susceptibility (volts)
λBP = .0022+((1.72810-5)(NP)) .Voltage ranges which will cause the part to tail. It unknown, use 0-1000 volts.
NP = Number of Package Pins





                                                                                                
5-7
MIL-HDBK-217F

5.4 MICROCIRCUITS, GaAs MMIC AND  DIGITAL DEVICES                                    

DESCRIPTION
Gallium Arsenide Microwave Monolithic Integrated Circuit (GaAs MMIC) and GaAs Digital Integrated Circuits using MOSFET Transistors and Gaia Based Metallization

FailUres/106 Hours

MMIC:Die Complexity Failure Rates-C1 Device Application Factor - πA
Complexity(No, of Elements) C1 Application πA
      1 to 100 4.5 MMIC Devices
   101 to 1000 7.2   Low nNoise & Low Power (≤ 100mW) 1.0
1. C1 accounts for the following activeelements :transistors, diodes.   Driver & High Power(>100mW) 3.0
  Unknown 3.0

Digital Devices All Digital Applications 1.0

Digital: Die Complexity Failure Rares-C1
Complexity C1 All Other Model Parameters
(No. of Elements) Parameter Refer to
        1 to 1000 25      πT Section 5.8
  1,001 to 10,000 51   
     C 2 Section 5.9
1. C1 accounts for the following active
    elements: transistors, codes.      πE.πL.πQ Section 5.10



































                                                                                              
5-8
MIL-HDBK-217F

我觉得你没有学会的东西还很多的........年轻人,你别以为在那些大

公司做过就以为你什么都懂了,,,,,,,,,天外有天.....

你说的对呀!天外有天.

呵呵, 年轻人就是这样, 说的不如做的.... 你既然可以保证设计寿命...以金卤灯电子镇流器为话题, 说说你从哪些方面去检验你的设计寿命...吹水总是很轻松的....

你很NB吗?

你在世界三大照明作过,,,,,,,,想必你的经验一定很丰富了,,,


说说看阿!!!!   能说个1,2,3,吗"

本人从不相信所谓的"设计寿命".... 所以特向你请教.... 至于OSRAM, GE 的产品在做了哪些试验后,就宣称可以保证3年...5年, 还是有体会, 但你宣称你的产品设计寿命达到5年...所以特向你请教...请不要保守...

上面那个小子,你说你是跑市场的,,,来这里讲技术方面的东西......给

你讲了,,,,,,  你也不懂哦,,,,,

你该走开了,,我看见你有点不舒服,,我卖我的技术,,,,,不买的别在这

里扯蛋!!!!!

至于设计寿命,,,你想怎么认为,就怎么认为吧!!!!!

我负责过市场,我也搞过HID EB开发... 但有人打着XX旗帜,总要给人点理由吧...国内有一小撮人老是说他是HID EB高手... 到目前...我还没有看到国内哪家公司的金卤灯电子镇流器通过了VDE认证....

如你对你的产品有信心能通过VDE认证, 我可以相信你可以联系的了买家...

有在这里扯皮的时间,还不如去实验室动动烙铁,,丢脸

按可靠性理论不叫设计寿命吧?
应该叫平均无故障工作时间—MTBF.
MTBF是可以计算的、但先要知道你用的元器件的失效率是多少.....?

如果我要批量定货(500只/250W),您能质保3年(正常使用)吗?设计寿命不能等同于实际使用寿命.

没事也来顶一下!

MTBF这种提法是比较科学的.现在我们的一些企业、销售人员,每当介绍产品的时候都提‘包用几年’,是这样说不是很严谨,希望把这个有误区的表述改正过来,作为搞技术的要带头,如果我们自己都弄错了,那人家销售人员、企业老板从我们这里会学到正确的东西吗?

MTBF和“包用几年”是完全不同的两个概念,不存在那一个更科学.对用户或者消费者来讲他关心的是“保用几年”或者“包用几年”的承诺.假如某产品MTBF等于100万小时,并不能说明消费者在买回去使用前100小时内不出现故障或损坏.如果出现损坏在没有保用承诺的条件下由于损坏造成的损失就只有消费者自己来承担.

‘包用几年’里面有个怎么用的问题,一天用二十四小时与一天用八小时都是用,用法不一样结果就不一样.但是,MTBF不管怎么用结果只有一个.用户关心产品的使用寿命、关心企业对产品质量的承诺,那么我们应当给一个明确的而不是模棱两可说法.
‘包用几年’是怎么来的,不就是根据平均无故障工作时间、根据一天用几个小时计算出来的吗,问题就在用户他一天用几个小时你又怎么知道呢.企业承诺产品使用寿命这么一个平均无故障工作概念,没有必要自以为是去计算一番再告诉用户,那是脱裤子打屁--多此一举.

设计寿命达不到平均使用寿命,那是错误的设计.一般是失效率参数取值和元件工况测试出现错误.

你说的道理是对的,任何一本可靠性理论方面的书里都会提到.现实中却是对自己产品质量没有信心就说自己产品设计寿命是多少多少小时,而不愿给出一个让消费者满意的质保期限.这种情况不但国内有,国外个别知名企业也有,这似乎不好让人理解,实际上跟产品的设计指导思想有相当大的关系.

怎样合作?

多少