xn_juan 发表于 2007-9-27 11:13:03

分立LED的MTBF计算方法

:):)

一点老大分享我的资料，大家随便看下喽！



MTBFFORDISCRETELEDSANDPHOTODIODES
ThecalculationofMeanTimeBetweenFailure(MTBF)isoftenrequiredasanaidinpredictingthereliabilityofelectronicequipmentunderdifferentoperatingconditions.ThevalueofMTBFforacomponentisbaseduponfailure-ratemodelswhichhavebeendevelopedinconjunctionwithMIL-HDBK-217E.TheMTBFisnotaguaranteeofuseableproductlifetime,butisaguideforplanningtheoperationaluseoftheequipment.Theaccuracyofthevaluescalculatedisdependentuponthevalidityofthemodels.Also,thevalueschosenfortheoperatingparametersmustberepresentativeoftheoperatingparametersduringactualuse.Inthecaseoffiberopticdatacommunicationequipment,anareaofprimaryconcernistheMTBFvaluesforthediscreteLightEmittingDiodes(LEDs)andphotodiodesusedinthefiberoptictransmittersandreceivers.

ThedeterminationofthepredictedMTBFforanLEDorphotodiodeisacalculationusingthepartfailure-ratemodelforoptoelectronicdevicesasfoundinsection5.1.3.10ofMIL-HDBK-217E.Thepartfailure-ratemodel,lP,isasfollows:where:ThevalueforMTBFisthendeterminedfrom:Threeoftheabovementionedfactorsareexplicitlydefinedinsection5.1.3.10ofMIL-HDBK-217E(lB,IIE,andIIQ).Valuesforthesefactors,alongwithdescriptionsofthevariousconditionsidentifiedbyMIL-HDBK-217Earediscussedinthisnote.Thefourthparameter,IIT,maybeobtainedeitherfromtablesprovidedinMIL-HDBK-217Eorfromcalculationsinvolvingparametricdataobtainedfromthedeviceduringactualorsimulatedoperation.IdentificationoftheseparametersandspecificdataapplicabletocomponentsmanufacturedbyHoneywellarealsocontainedinthisapplicationnote.

ThereareseveralsamplecalculationstoaidtheuserindeterminingMTBFvaluesfortheparticularcomponentswhichheisconsidering.Inaddition,thereareanumberoftablesincludedinwhichMTBFvaluesarelistedforvarioustypesofdevicesunderdifferentoperatingconditions.BASEFAILURERATEThedevicebasefailure-rate,lB,isgiveninTable5.1.3.10-3ofMIL-HDBK-217E.ThevaluesforLEDandphotodiodesareshownbelow.BaseFailure-Rate(fromMIL-HDBK-217E,Table5.1.3.10-3)QUALITYFACTORThequalityfactorisgiveninTable5.1.3.10-4ofMIL-HDBK-217E.Thisisreproducedbelowalongwithabriefdescriptionofthevariousqualitylevels.QualityFactors(fromMIL-HDBK-217E,Table5.1.3.10-4)QualityLevelIIQDescriptionJANTXV0.001FulltestingasdefinedbyMIL-S-19500includingScreeningandGroupsA,B,andC.JANTX0.02IdenticaltoJANTXVexceptdoesnotincludethe100%precapvisualinspectioncontainedinScreening.JAN0.1TestingasdefinedbyMIL-S-19500includingGroupsA,B,andC,butnotincludingScreening.LOWER0.5AppliestoallhermeticpackagedLEDsandphotodiodes.PLASTIC1.0Appliestoalldevicesencapsulatedwithorganicmaterials.Productsmeetinganyofthequalitylevelsdefinedinthequalityfactorstable(MIL-HDBK-217E,Table5.1.3.10-4)areavailablefromHoneywell.WhilethereareveryfewfiberoptictypeproductsdefinedbyaslashsheettoMIL-S-19500,atestprogramcanbedesignedwhichwillcarryouttheintentionofMIL-S-19500foranyofthe"metalwindowcan"deviceswhichHoneywelloffers.ApplicationNoteCalculatingMeanTimeBetweenFailureforDiscreteLEDsandPhotodiodesP=BTEQfailures106hoursT=temperaturefactorE=environmentalfactorQ=qualityfactorB=basefailure-ratefailures106hoursMTBF=1PforasingleLED0.0011failures106hoursforaphotodiodeand0.00065failures106hoursB=B=©HoneywellEuropeS.A.Honeywellreservestherighttomakechangesinordertoimprovedesignandsupplythebestproductspossible.       


[本帖最后由paulyu于2007-9-2711:19编辑]

paulyu 发表于 2007-9-27 11:21:59

回复 #1 xn_juan 的帖子

xn_juan,發表下載的東西，盡可能的摘要一些內容出來，便于下載。

xn_juan 发表于 2007-9-27 14:22:57

en~

:)好的啊！
我以后注意！

kyvenger 发表于 2007-9-29 16:12:06

谢
谢

aboo 发表于 2008-1-26 11:26:18

不错哦。thanks

zhanghjspace 发表于 2008-10-21 12:35:43

先看看再说，呵呵

liguang304 发表于 2008-10-22 12:03:34

好东西,珍藏!!!

danlings 发表于 2009-8-26 19:49:48

我晕啊，英文的啊，密密麻麻的...

deadxiaoh 发表于 2010-7-13 17:13:56

谢谢分享！！！！！！！！

scutzhj 发表于 2010-8-12 11:38:25

下载看了一下，挺好的学习资料，非常感谢楼主
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