Practical Electronic Reliability Engineering, Softcover reprint of the original 1st ed. 1992
Getting the Job Done from Requirement through Acceptance

This book is intended for the engineer or engineering student with little or no prior background in reliability. Its purpose is to provide the background material and guidance necessary to comprehend and carry out all the tasks associated with a reliability program from specification generation to final demonstration of reliability achieved. Most available texts on reliability concentrate on the mathematics and statistics used for reliability analysis, evaluation, and demonstration. They are more often suited more for the professional with a heavier mathematical background that most engineers have, and more often than not, ignore or pay short-shrift to basic engineering design and organizational efforts associated with a reliability program. A reliability engineer must be familiar with both the mathematics and engineering aspects of a reliability program. This text: 1. Describes the mathematics needed for reliability analysis, evaluation, and demonstration commensurate with an engineer's background. 2. Provides background material, guidance, and references necessary to the structure and implementation of a reliability program including: ? identification of the reliability standards in most common use ? how to generate and respond to a reliability specification ? how reliability can be increased ? the tasks which make up a reliability program and how to judge the need and scope of each; how each is commonly performed; caution and comments about their application.

1. Reliability: An Introduction To Concepts and Terms.- 1.1 Reliability and Failure: The Concept.- 1.2 Reliability: Its Origin.- 1.3 Reliability: A Quantitative Definition.- 1.4 Reliability: Comprehension of Definitions, Measures, and Specifications.- 2. Application of Failure Distributions to Reliability.- 2.1 Distributions Associated with Failure of Items and Equipment.- 2.1.1 The Exponential Distribution.- 2.1.2 The Weibull Distribution.- 2.1.3 The Log-Normal Distribution.- 2.1.4 The Gamma Distribution.- 2.1.5 Equipment-Level Prediction Using a Hybrid Approach.- 2.2 Distributions Used in Equipment and System Modeling.- 2.2.1 The Poisson Distribution as a Modeling Tool.- 2.2.2 The Binomial Distribution as a Modeling Tool.- 2.2.3 The Normal Distribution as a Modeling Tool.- 2.3 Distributions Used for Reliability Demonstration and Measurement.- 2.3.1 The Poisson Distribution in Demonstration and Measurement.- 2.3.2 The Weibull Distribution in Demonstration and Measurement.- 2.3.3 The Gamma Distribution in Demonstration and Measurement.- 2.3.4 The Chi-Square Distribution in Demonstration and Measurement.- 2.3.5 The Binomial Distribution in Demonstration and Measurement.- 2.4 The Relationships Among Distributions.- 3. The Customerߣs Role in Reliability Programs.- 3.1 How Much Reliability Do We Need?.- 3.1.1 Examining the Need for the Item.- 3.1.2 General Nature of a Requirement.- 3.1.3 Generation of Reliability Requirements.- 3.2 Reliability Warranties in Lieu of Requirements.- 3.2.1 When a Warranty/Guarantee Should be Considered.- 3.2.2 Composition of a Warranty/Guarantee.- 3.3 Structuring Program Requirements: The Five Factors.- 3.3.1 The Five Factors and the Acquisition Process.- 3.3.2 The Five Factors and Equipment System Characteristics.- 3.3.3 The Five Factors and Procurement Strategy.- 3.4 Communicating with the Contractor: Specifications and Standards.- 3.4.1 Transforming General Reliability Program Factors to Engineering Tasks.- 3.5 Reliability Standards and Handbooks That You Should Know About.- 3.5.1 Mil-Std-785: “Reliability Programmer Systems and Equipment Development/Production.- 3.5.2 Mil-M-38510: “General Specifications for Micro Electronics”.- 3.5.3 Mil-Std-883: “Test Methods and Procedures for Micro Electronics”.- 3.5.4 Mil-Std-756: “Reliability Modeling and Prediction”.- 3.5.5 Mil-Hdbk-217: “Reliability Prediction of Electronic Equipment”.- 3.5.6 Mil-Hdbk-338: “Electronic Reliability Design Handbook”.- 3.5.7 Mil-Std-2164 (EC): “Environmental Stress Screening Process for Electronic Equipment”.- 3.5.8 DOD-Hdbk-344 (USAF): “Environmental Stress Screening of Electronic Equipment”.- 3.5.9 Mil-Std-2155 (AS): Failure Reporting Analysis and Corrective Action System.- 3.5.10 Mil-Std-1629: “Procedures for Performing a Failure Mode Effects and Criticality Analysis”.- 3.5.11 Mil-Hdbk-251: “Reliability/Design Thermal Applications”.- 3.5.12 Mil-Std-781: “Reliability Testing for Engineering Development, Qualifications and Production”.- 3.5.13 Mil-Hdbk-781: “Reliability Test Methods, Plans and Environments for Engineering Development, Qualification and Production”.- 3.5.14 Mil-Hdbk-189: “Reliability Growth Management”.- 3.5.15 Mil-Std-1521 (USAF): “Program Reviews”.- 3.5.16 Mil-Std-721: “Definition of Terms for Reliability and Maintainability”.- 3.6 Customer Responsibilities.- 3.6.1 Customer Responsibilities: Preparing for the Program.- 3.6.2 Customer Responsibilities in the Application of Mil-Stds.- 3.6.3 Customer Responsibilities Irrespective of Standards Used.- 3.6.4 Structuring the Reliability Program.- 3.6.5 Customer Responsibilities: Providing Information and Detail.- 3.6.6 Customer Responsibilities to the Customer Organization.- 4. The Role of the Contractor/Developer in Formulating Reliability Approaches and Needs.- 4.1 The Reliability Organization: Form and Responsibilities.- 4.2 Reliability Technical Planning: A Developerߣs View.- 4.2.1 Cycling Constraints: Reliability Multipliers.- 4.2.2 Allowable Downtime: Reliability Multipliers.- 4.2.3 Fault Tolerance: Reliability Multipliers (Functional or Replicative).- 4.2.4 Maintenance Allowed: Reliability Multipliers.- 4.2.5 Technology Advances: Reliability Multipliers.- 4.2.6 Integration and Sharing of Resources.- 4.2.7 Use of Higher-Reliability Parts.- 4.3 Formulating the Reliability Design/Development Approach.- 4.4 Correlating the Reliability Program with the System Engineering Process.- 4.4.1 Demonstration/Validation Phase of Development.- 4.4.2 The Full-Scale Engineering Phase Development.- 4.4.3 The Production Phase of a Development Program.- 4.5 The Role of the Developer/Producer After Contract Award.- 5. Rudimentary Probabilistic/Statistical Concepts Used in Performance of Reliability Program Tasks.- 5.1 The Mean.- 5.2 A Probability.- 5.3 An Expected Value.- 5.4 An Independent Event.- 5.5 A Conditional Event.- 5.6 Mutually Exclusive Events.- 5.7 The Addition Law for Probabilities.- 5.8 The Multiplication Law for Probabilities.- 5.9 Addition and Multiplication Guides for Distributions.- 5.10 The Tchebychev Inequality.- 6. The Parts Program—What You Should Know, What You Can Do.- 6.1 Reliability and Quality Interfaces and Effects.- 6.2 Rationale and Use of Part Specifications and Standards.- 6.3 Applying Controls to Enhance Part Reliability and Quality.- 6.3.1 When Tri-service Standards and Specifications Are Not Applicable as Controls.- 6.4 Improving the Reliability and Quality of an Existing Part.- 6.5 Dealing with New or Unique Parts.- 6.6 Effects of Part Defects and Tolerance Levels on Assembly, Quality, and Equipment Reliability.- 6.6.1 Part Defects and the Quality and Reliability of Assemblies.- 6.6.2 Part Tolerance vs. Assembly Quality and Reliability.- 6.6.3 Using Statistical Design Techniques to Reduce Rework.- 6.6.4 Part Tolerances and Reliability.- 6.7 The Parts Program: Things a Reliability Engineering Manager Should Know.- 6.7.1 Part Selection Criteria.- 6.7.2 Quality Differences Between Mil-Std and Non-Mil-Std Parts.- 6.7.3 Part Acquisition/Procurement.- 7. Providing a Basis for Detailed Design. The Reliability Block Diagram and Reliability Apportionment.- 7.1 The Reliability Block Diagram: The Starting Point of Many Reliability Activities.- 7.2 Reliability Apportionment/Allocation in the Development Process.- 7.2.1 What Reliability Apportionment and Allocation Is.- 7.2.2 Reliability Apportionment: The First Cut.- 7.2.3 Reliability Apportionment with Respect to Criticality.- 7.2.4 Reliability Control, A Key Element in Apportionment.- 7.2.5 Reliability Apportionment with Respect to Identified Engineering Alternatives.- 7.2.6 Reliability Cost/Payoff Approach to Apportionment.- 8. Reliability Prediction During the Development Process.- 8.1 Initial Reliability Prediction Approaches.- 8.1.1 Extrapolation Approaches to Initial Reliability Estimation.- 8.2 Intermediate Design-Level Predictions: Module Count Methods.- 8.3 Intermediate to Detailed Approaches to Prediction. Part Count Methods.- 8.4 Detailed Reliability Prediction Approaches.- 8.4.1 Detailed Reliability Prediction: A Failure Rate Approach.- 8.4.2 Detailed Reliability Prediction: Deterministic Approach.- 8.5 Special Considerations in Predicting Reliability.- 8.5.1 Duty-Cycle Mode Effects on Reliability.- 8.5.2 Multifunction Systems Reliability Prediction.- 8.5.3 Unequal Operating Times Associated with System Components.- 8.5.4 Accounting for Stresses That Are Mission Phase-Dependent in Reliability Prediction.- 8.5.5 Accounting for Failure Rates of Nonoperating Systems.- 8.5.6 Accounting for Operational Influences on Reliability.- 9. Reliability Analysis and Evaluation of Series-Connected Systems.- 9.1 Mission Reliability Measures Used for Evaluation.- 9.1.1 Components with Exponential Failure Distributions.- 9.1.2 Components with Weibull Failure Distributions.- 9.2 Evaluating “Mean Time” Measures of Reliability.- 9.2.1 “Mean Time” Measures Associated with an Exponential Distribution of Failures.- 9.2.2 “Mean Time” Measures Associated with Items with Weibull Distributions of Failure.- 9.3 Evaluating Availability Measures of Reliability.- 9.3.1 The System States: What They Are and How They Can Be Identified.- 9.3.2 Steady-State Availability in General.- 9.3.3 Dynamic Measures Associated with Availability.- 9.3.4 Availability When Maintenance Is Not Performed at Failure.- 9.4 Combined Measures of Reliability and Availability Effectiveness.- 10. Reliability Analysis and Evaluation of Redundant or Fault-Tolerant Systems.- 10.1 Redundant Systems Which Are Not Maintained.- 10.1.1 Full-On Redundancy: The Single-Survivor Subsystem; Perfect Sensing and Switching.- 10.1.2 Full-On Redundancy: Multiple-Survivor Subsystem/System; Perfect Sensing and Switching.- 10.1.3 Full-On Redundancy: An Alternate Way of Understanding and Evaluating Mean Time to First Failure.- 10.1.4 Full-On Redundancy: Taking Into Account Imperfect Sensing and Switching.- 10.1.5 Standby Redundancy: The Single-Survivor Subsystem; Perfect Sensing and Switching.- 10.1.6 Standby Redundancy: The Multiple-Survivor Subsystem; Perfect Sensing and Switching.- 10.1.7 Standby Redundancy: An Alternate Way of Understanding and Evaluating Mean Time to Failure.- 10.1.8 Standby Redundancy: Taking into Account Imperfect Sensing and Switching.- 10.1.9 Comparing Full-On and Standby Redundancy Effects.- 10.2 Redundant Subsystems Which Are Periodically Maintained.- 10.2.1 Mean or Average Uninterrupted Life Over An Operating Period (AUL).- 10.2.2 Mean Uninterrupted Total Operating Time to First Failure (MUOT).- 10.3 Operationally Maintained Redundant Subsystems and Systems: Availability and Reliability.- 10.3.1 Steady-State Availability for Full-On Redundant Subsystems and Systems.- 10.3.2 Steady-State Availability for Standby Redundant Subsystems and Systems.- 10.3.3 Steady State MTBF: A Subsystem/System Reliability Measure.- 11. Reliability Design Technologies.- 11.1 Failure Modes and Effects Analysis (FMEA).- 11.1.1 The Tabular FMEA: Makeup and Process.- 11.1.2 The Fault Tree Analysis: Makeup and Process.- 11.2 Sneak Circuit Analysis: Its Link to Reliability; What It Is and Its Payoff.- 11.2.1 Applications of Sneak Circuit Analysis—On What and When?.- 11.2.2 Sneak Circuit Analysis: The Process.- 11.2.3 Sneak Circuit Analysis: Minimizing Occurrences.- 11.3 Thermal Management and Analysis: Their Roles in Reliability Programs.- 11.3.1 The Relationship of Temperature to the Reliability of Electronic Parts.- 11.3.2 Incorporating Thermal Design/Analysis into the Reliability Program: Theory and Practice.- 11.3.3 General Insights, Guides, and Rules About Thermal Design That a Reliability Engineer Should Know.- 11.4 Reliability Parts Derating: Its Logic and Practice.- 11.4.1 Defining Derating Levels: Establishing a Derating Window.- 11.4.2 Choosing Derating Levels: Rules of Thumb.- 11.5 Failure Reporting and Corrective Action System (FRACAS).- 11.6 Reliability Growth: A Means for Improving Reliability Design.- 11.6.1 Reliability Growth: Scoping a Reliability Growth Test Task.- 11.6.2 Reliability Growth: Its General Mechanics and Considerations.- 11.6.3 Reliability Growth: The Analysis Process.- 11.6.4 Reliability Growth: Performance and Analyses The Duane Model (Method).- 11.6.5 Reliability Growth: Performance and Analysis The AMSAA Method.- 11.7 Environmental Stress Screening: Improving Reliability by Removing Latent Defects.- 11.7.1 Clues to When An ESS Program Will Pay Off.- 11.7.2 The Mechanics of an ESS Program.- 12. Reliability Measurement and Demonstration.- 12.1 Reliability Measurement and Estimation.- 12.1.1 Confidence Bounds and Intervals: What They Are.- 12.1.2 Reliability Measurement of a “Single-Shot” or Go-No Go Operation.- 12.1.3 Measuring the Probability of Successful Use When the Reliability of an Item is Known.- 12.1.4 Measuring the Mean Time to Failure for Items Having Exponential Distributions of Failure.- 12.1.5 Measuring the Mean Time to Failure for Items Having Nonconstant Hazards.- 12.2 Reliability, Qualification, Demonstration, and Test.- 12.2.1 Consumer and Producer Risks: What They Are.- 12.2.2 Structuring a Demonstration Plan to Your Needs.- 12.2.3 Qualification Tests on Parts or Components: Acceptable Quality Level (AQL) and Lot Tolerance Percent Defective (LTPD).- 12.2.4 Demonstrating a Development Requirement for Items Having An Exponential Distribution Failure.- 12.2.5 Demonstrating a Production Requirement for Items Having Exponential Distribution of Failure.- 12.2.6 Reliability Demonstration for Items Having Nonconstant Hazards.- A0 A General Reliability Expression.- Al An Expression for Reliability When Time to Failure Follows an Exponential Distribution 544.- A2 An Expression for Reliability When Time to Failure Follows a Weibull Distribution.- A3 The Gamma Distribution and the Poisson Distribution.- A4 The Derivation of Mean Time to First Failure (MTFF) and Mean Time to Failure (MTTF).- A7 Determining the Distribution of an Estimator of MTTF.- A8 Evaluating the Fraction of Defective Units Which Result From the Use of Part Populations with Various Levels of Defects.- A9 Device Failure Rate/Complexity Relationships.- A10 The Variance Associated with Equipment Failure-Rate Prediction Versus the Variance Associated with Part Failure-Rate Prediction.- A11 Reliability Expressions Resulting and Failure-Rate Prediction Based on Average Hazard Over an Established Period of Time.- A12 Calculating the Effects of Nonoperating Failure Rates on the Number of Failures Predicted for Operating Periods.- A13 Mission Reliability for a System Made Up of n Components Each Having an Exponential Distribution or Weibull Distribution.- A14 Effect on State Availability of the Strategy of Shutting Down the System at the First Component Failure.- A15 Derivation of Mean Time to Failure for Full-On Redundant Systems.- A16 Availability Expressions for Maintained Standby Redundant Subsystems.- A17 Steady-State MTBF and Mean Time to Failure of Maintained Full-On Redundant Subsystems.- A18 Steady-State MTBF and Mean Time to Failure of Maintained Standby Redundant Subsystems.- A19 Approximate Distribution of a Proportion for Large Sample Sizes.- A20 Transformation of the Weibull Distribution to an Exponential Form to Facilitate Reliability Measurement and Demonstration.