Practical Electronic Reliability Engineering

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 Customer's 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 Developer's 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.