# SAE J1213_2v001

SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.QUESTIONS REGARDING THIS DOCUMENT: (724) 772-8512 FAX: (724) 776-0243TO PLACE A DOCUMENT ORDER; (724) 776-4970 FAX: (724) 776-0790SAE WEB ADDRESS http://www.sae.orgCopyright 1988 Society of Automotive Engineers, Inc.All rights reserved. Printed in U.S.A.SURFACEVEHICLE400 Commonwealth Drive, Warrendale, PA 15096-0001STANDARDSubmitted for recognition as an American National StandardJ1213/2ISSUEDOCT88Issued 1988-10GLOSSARY OF RELIABILITY TERMINOLOGY ASSOCIATED WITH AUTOMOTIVE ELECTRONICSForeword—This Document has not changed other than to put it into the new SAE Technical Standards BoardFormat.This glossary has been compiled to assist, by serving as a reference, in the communication between theautomotive electronics engineer and the reliability engineer.1. Scope—This compilation of terms, acronyms and symbols was drawn from usage which should be familiar tothose working in automotive electronics reliability. Terms are included which are used to describe how items,materials and systems are evaluated for reliability, how they fail, how failures are modeled and how failures areprevented. Terms are also included from the disciplines of designing for reliability, testing and failure analysisas well as the general disciplines of Quality and Reliability Engineering. This glossary is intended to augmentSAE J1213, Glossary of Automotive Electronic Terms.2. References2.1 Applicable Publications—The following publications form a part of this specification to the extent specifiedherein. Unless otherwise indicated, the latest version of SAE publications shall apply.2.1.1 SAE PUBLICATION—Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.SAE J1213—Glossary of Automotive Electronic TermsSAE AE-9 1987—Automotive Electronics Reliability Handbook2.2 Related Publications—A listing of applicable military and other organizational reference documents, fromwhich many of these terms and definitions were drawn, is provided as a source of alternate or relateddefinitions.MilitaryMIL-STD-105D—Sampling Procedures and Tables for Inspection by AttributesMIL-STD-202E—Test Methods for Electronic and Electrical Component PartsMIL-HDBK-217D—Reliability Prediction of Electronic EquipmentMIL-STD-280A—Definitions of Item Levels, Item Exchangeability, Models, and Related TermsMIL-STD-414—Sampling Procedures and Tables for Inspection by Variables for Percent DefectiveMIL-STD-756B—Reliability Models and PredictionMIL-STD-781C—Reliability Design Qualification and Production Acceptance Tests — ExperimentalSAE J1213/2 Issued OCT88-2-MIL-STD-790B—Reliability Assurance Program for Electronic Parts SpecificationMIL-STD-810C—Environmental Test MethodsMIL-STD-883B—Test Methods and Procedures for MicroelectronicsMIL-STD-1313—Microelectronics Terms and DefinitionsMIL-Q-9858A—Quality Program RequirementsAR-92—Quality Program RequirementsMIL-S-195001—Semiconductor Devices, General Specification forMIC M38510D—Microcircuits, General Specifications forMIL-STD-470—Maintainability Program Requirements for Systems and EquipmentsMIL-STD-471A—Maintainability Verification/Demonstration/EvaluationMIL-HDBK-472—Maintainability PredictionMIL-STD-891—Contractor Parts Control and Standardization ProgramMIL-STD-701—Preferred and Guidance List of Semiconductor DevicesMIL-STD-198A—Selection and Use of CapacitorsMIL-STD-199B—Selection and Use of ResistorsMIL-STD-1562—List of Standard MicrocircuitsMIL-STD-976—Certification Requirements for JAN MicrocircuitsEIAReliability Bulletin No. I—A General Guide for Technical Reporting of Electronic Reliability MeasurementReliability Bulletin No. 4A—Reliability QualificationsReliability Bulletin No. 5—Equipment Reliability Specification GuidelineReliability Bulletin No. 10—Selection and Validation of Low Population and/or State of the Art PartsReliability Bulletin No. 9—Failure Mode and Effects AnalysesReliability Bulletin No. 8—Equipment Burn-InEngineering Bulletin No. 17—User Guidelines for Quality and Reliability Assurance of LSI ComponentsEngineering Bulletin No. 11—User Guidelines for Microelectronic Reliability EstimationJEDEC Standard No. 22—Test Methods and Procedures for Solid State Devices Used in Transportation/Automotive ApplicationsOtherASQC 1973—Glossary and Tables for Statistical Quality ControlASQC Procurement Quality Control - 2nd EditionANSI/ASQC A3-1978—Quality Systems TerminologyANSI/ASQC A2-1978—Terms, Symbols and Definitions for Acceptance SamplingANSI/ASQC A1-1978—Definitions, Symbols, Formulas and Tables for Control ChartsHow to Speak Fluent Quality- National Semiconductor Co.RDH 376—Reliability Design Handbook - Reliability Analysis CenterWPS-1—Analysis Techniques for Mechanical Reliability - Reliability Analysis Center1987 Desk Manual- Microelectronic Manufacturing and TestingThe American Heritage Dictionary- 2nd College Edn. 1982 Houghton Mifflin Co.3. Definitions3.1 Accelerated Life Test—A life test under test conditions that are more severe than usual operating conditions.It is necessary that a relationship between test severity and the probability distribution of life be ascertainable.3.2 Acceleration Factora. The factor by which the failure rate can be increased by an increased environmental stress.b. The ratio between the times necessary to obtain the same portion of failure in two equal samplesunder two different sets of stress conditions, involving the same failure modes and mechanisms.SAE J1213/2 Issued OCT88-3-3.3 Accept/reject Test—A test, the result of which will be the action to accept or reject something, for example, anhypothesis or a batch of incoming material.3.4 Acceptable Quality Level (AQL)—The maximum percent defective which can be considered satisfactory as aprocess average, or the percent defect whose probability of rejection is designated by α.3.5 Acceptance Number—The largest number of defects that can occur in an acceptance sampling plan and stillhave the lot accepted.3.6 Acceptance Sampling Plan—An accept/reject test whose purpose is to accept or reject a lot of items ormaterial.3.7 Accessibility—A measure of the relative ease of admission to the various areas of an item.3.8 Achieved Reliability—The reliability demonstrated at a given point in time under specified conditions of useand environment.3.9 Activation Energya. The energy level at which a specific microelectronic failure mechanism becomes active (in electron volts).b. The slope of the time temperature regression line in the Arrhenius equation (in electron volts).3.10 Active Element—A part that converts or controls energy, for example, transistor, diode, electron tube, relay.3.11 Active Element Group—An active element and its associated supporting (passive) parts, for example, anamplifier circuit, a relay circuit, a pump and its plumbing and fittings.3.12 Aging—The effect whereby the probability density function of strength is changed (strength is reduced) withtime.3.13 Allocation—The process of assigning reliability requirements to individual units to attain the desired systemreliability.3.14 Alpha Particle Induced Soft Errors—Integrated circuit memory transient errors due to emission of alphaparticles during radioactive decay of uranium or thorium contamination in the IC packaging material.3.15 Ambient—Used to denote surrounding, encompassing, or local conditions. Usually applied to environments,for example, ambient temperature, ambient pressure.3.16 Apportionment—Synonym of Allocation.3.17 Arithmetic Mean—The arithmetic mean of n numbers is the sum of the n numbers, divided n.3.18 Arrhenius Model—A mathematical representation of the dependence of failure rate on absolute temperatureand activation energy. The model assumes that degradation of a performance parameter is linear with time withthe failure rate a function of temperature stress. The temperature dependence is taken to be the exponentialfunction:SAE J1213/2 Issued OCT88-4-(Eq. 1)where:θ1 = mean time to failure at T1θ2 = mean time to failure at T2T = junction temperature in KE = activation energy in eVk = Boltzman’s constant (8.617 105 eV/K)3.19 Arrhenius Acceleration Factor—The acceleration factor F is the factor by which the time to fail can bereduced by increased temperature.(Eq. 2)3.20 Assessmenta. A critical appraisal, including qualitative judgments about an item, such as importance of analysisresults, design criticality and failure effect.b. The use of test data and/or operational service data to form estimates of population parameters and toevaluate the precision of these estimates.3.21 Attribute—A term used to designate a method of measurement whereby units are examined by noting thepresence (or absence) of some characteristic or attribute in each of the units in the group under considerationand by counting how many units do (or do not) possess it. Inspection by attributes can be of two kinds – eitherthe unit of product is classified simply as defective or nondefective, or the number of defects in the unit ofproduct is counted, with respect to a given requirement or set of requirements.3.22 Attribute Testing—Testing to evaluate whether or not an item possesses a specified attribute.3.23 Automatic Test Equipment (ATE)—Test equipment that contains provisions for automatically performing aseries of pre programmed tests.3.24 Availability (Operational Readiness)—The probability that at any point in time the system is either operatingsatisfactorily or ready to be placed in operation on demand when used under stated conditions.3.25 Average—A general term. It often means arithmetic mean, but can refer to s-expected value, median, mode,or some other measure of the general location of the data values.3.26 Average Outgoing Quality (AOQ)—The average quality of outgoing product after 100% inspection of rejectedlots, with replacement by good units of all defective units found in inspection.3.27 Average Outgoing Quality Limit (AOQL)—The maximum average outgoing quality (AOQ) for a samplingplan.3.28 Bake-out—To subject an unsealed item to an elevated temperature to drive out moisture and unwanted gasesprior to other process or sealing.3.29 Bathtub Curve—A plot of failure rate of an item (whether repairable or not) vs. time. The failure rate initiallydecreases, then stays reasonably constant, then begins to rise rather rapidly. It has the shape of a bathtub.Not all items have this behavior.θ1 θ2 exp Ek⁄()1 T2 1 T1⁄–⁄()[]=F θ1 θ2⁄ Ek⁄()1 T2 1 T2⁄–⁄()exp==SAE J1213/2 Issued OCT88-5-3.30 Biasa. The difference between the s-expected value of an estimator and the value of the true parameter.b. Applied voltage.3.31 Binomial Distribution—The probability of r, or fewer successes in n independent trials, given a probability ofsuccess p in a single trial, is given by the cumulative binomial distribution:(Eq. 3)3.32 Binomial Function—The probability of exactly x successes in n independent trials, given a probability ofsuccess p in a single trial, is given by the binomial probability function:(Eq. 4)3.33 Bonda. An interconnection which performs a permanent electrical and/or mechanical function.b. To join with adhesives.3.34 Bond Lift Off—The failure mode whereby the bonded lead separates the surface to which it was attached.3.35 Bond Strength—In wire bonding, the pull force at rupture of the bond interface.3.36 Breadboard Model—A preliminary assembly of parts to test the feasibility of an item or principle withoutregard to eventual design or form. Usually refers to a small collection of electronic parts.3.37 Burn-in—The initial operation of an item to stabilize its characteristics, and to minimize infant mortality in thefield.3.38 Capabilitya. A measure of the ability of an item to achieve mission objectives given the conditions during themission.b. The spread of performance of a process in a state of statistical control; the amount of variation fromcommon causes identified after all special causes of variation have been eliminated.3.39 C Chart—Control chart for number of nonconformities observed in some specified inspection. The unitsshould be alike in size and in the apparent likelihood of the existence of the nonconformity, in order that thearea of opportunity for nonconformity be constant from unit to unit.3.40 Central Line—The line on a control chart that represents the average or median value of the items beingplotted. It is shown as a solid line.3.41 Checkout—Tests or observations on an item to determine its condition or status.3.42 Coefficient Of Variation—The standard deviation divided by the mean, multiplied by 100 and expressed as apercentage.3.43 Complexity Level—A measure of the number of active elements required to perform a specific systemfunction.Pr xr≤()F (r; p, n) nxpx 1p–()nx–x 0=r∑==xpn,;()nxpx 1p–()nx– x,= 0, 1, 2, …n0 p 1≤≤=SAE J1213/2 Issued OCT88-6-3.44 Component—A self-contained combination of parts, subassemblies, or assemblies which perform a distinctivefunction in the overall operation of an equipment. Often used interchangeably with (electronic) part.3.45 Confidence—A specialized statistical term referring to the reliance to be placed in an assertion about thevalue of a parameter of a probability distribution.3.46 Confidence Coefficienta. A measure of assurance that a statement based upon statistical data is correct.b. The probability that an unknown parameter lies within a stated interval or is greater or less than somestated value.3.47 Confidence Interval—The interval within which it is asserted that the parameter of a probability distributionlies.3.48 Confidence Level(Eq. 5)where:a = the risk (%)3.49 Confidence Limit—A bound of a confidence interval.3.50 Consistency—A statistical term relating to the behavior of an estimator as the sample size becomes verylarge. An estimator is consistent if it converges to the population value as the sample size becomes large.3.51 Constant Failure Ratea. A term characterizing the instantaneous failure rate in the middle, or “useful life“ period of the BathtubCurve model of item life.b. A term characterizing the hazard rate, h(t), of an item having an exponential reliability function.3.52 Contamination—A general term used to describe an unwanted material that adversely affects the physical orelectrical characteristics of an item.3.53 Continuous Sampling Plan—In acceptance sampling, a plan intended for application to a continuous flow ofindividual units of product that involves acceptance or rejection on a unit-by-unit inspection and sampling.Continuous sampling pla