西门子可靠性培训资料.ppt
M.Chbat,S.Eberlin,M.Tochtermann,T.Juhnke,hiT 7500 Multi-Haul DWDM system Product Reliability Update Processes,Status,and Measures,Sept 15,2004,Siemens Reliability Process Overview,Card FIT Rate,Feedback from Field Return Rate,Product Reliability Assurance Process,Reference:Siemens standard;in agreement with international standards IEC 61709,product definition,product development,product delivered,requirements aligned with technology basis failure rate allocation to individual cards involvement of component engineering&QA,card failure rates on basis of parts listscomponent rating by designnew&critical components specificationnew components&supplier audits,in production failure controlfield return analysis&threshold monitoringconservative data based on predicted valuesregular component supplier audits,Reliability Control and Improvement,Cross-functional team established to install focused program Close interaction with the supplier for design,technology and processEarly failure monitoring and feedback in development phase Extended testing including temperature cycling in productionDetailed failure monitoring in production for early corrective action,Predicted FIT rates vs.field return FIT rates,Field return FIT rate inherently is(!)lower than predicted FIT rate spare parts dont contribute to FMAnon-installed equipment at certain carrierslow channel count for many yearstemperature for FIT estimation probably higher than in realitymargin(e.g.,due to low channel count,low PMD,BOL)can mask performance degradation,Functional Partition of OLI,Optical amplification via EDFA gain blockPump diodesMonitor diodesEDF-HeaterInternal Gain SwitchOSC splitting functions asAdd/Drop of the OSC channel using wavelength selective couplersSplitting of monitor signals at the input and output port and at intermediate measurement pointsSpectral shaping of the signal using aVOA for setting the EDFA to an optimized operating pointGTC for tilt compensationOptical monitor ports at input and output for signal supervisionAPSD circuitryGain Control and Supervision(DSP,on-board processor)Electrical components for control and power supplyMechanics including PCB,The bathtub curve:Failure rates l via time T,The unit of the failure rate l is a FIT(Failure in Time;1 FIT=1 Failure per 109h)!,Bathtub Curve,IEC 61709:Electronic components ReliabilityReference conditions for failure rates and stress models for conversion(no basic failure rates),Relationship between StandardsSIEMENS standard SN29500/IEC61709 compared to SR-332,SR-332:Reliability Prediction Procedure forElectronic Equipment,SN29500:Failure rates of componentsExpected values(This is in addition to IEC 61709),a)Climatic and mechanical stresses per IEC 721-3-3(see next slide)multiplying factors for environmentalconditionsb)Quality factortested components SN725004 quality levels knownc)Temperature and electrical stressby reference conditions IEC 61709given reference conditions and conversion(SR-332),IEC 61709:Electronic components Reliability Reference conditions for failure rates and stress models for conversion,The definitions,reference conditions and conversion models used in the IEC 61709 fullycorrespond with the already existing SIEMENS standard SN 29500 method.,Details:SIEMENS Standard SN29500 and IEC61709,FIT Rates of Individual Electrical Components(1),Voltage dependence and Current dependence,UOperating voltage in VUrefReference voltage in VUmaxRated voltage in VC1Constant in(1/V)C2C2,C3Constants(1).Digital CMOS Families,Contactors(2).Others,IOperating current in AIrefReference current in AImaxRated current in AC4,C5Constants,FIT Rates of Individual Electrical Components(2),AConstantEa1,Ea2Activation energies in eVTU,refReference ambient temperature in KT1Reference junction*)-(comp.*)-)temperature in KT2Actual junction*)-(comp.*)-)temperature in K*)Depends on type of component,see also SN 29500,Part 1,Capt.4.3,Temperature dependence,The expected failure rate of a HW-unit can be calculatedby adding the expected failure rates of the components:,Details:Total Reliability and Total Failure Rate of Unit,Siemens Reliability Process Overview,Card FIT Rate,Feedback from Field Return Rate,Estimation of FIT Rates for Optical Components,In parallel to the qualification cross-check detailed discussions take place with the vendorWhat is the estimate of the vendor?How did he reach his estimate?What is the FIT rate of sub-components and PCBAs of the module?Results of the cross-qualification are taken into account(failures,corrective actions,changes)The estimation of the vendor and the expertise of qualification team lead to the Siemens estimate(not necessarily the same as the vendors estimate)Field returns are taken into account when available and compared to the estimateFIT rates are adapted accordingly(repetitive process),Example of FIT Rate Adaption:EDFA w/5 pumps,First estimate in 2001:6000 FIT(complete new design incl.new Pumps,no experience at SIEMENS side)New vendors(new spec.)were qualified by CoC Optics and the CoC process took placeEstimates by two vendors:3500-4800 FITReduction to 5000 FIT beginning of 2004Quality improvement discussions with the vendors ongoingCheck with field returns:1600 FITReduction to 4000 FIT(Siemens estimate)in April of 2004Continuously monitoredSimilar process with EDFAs(2 pumps)lead to an estimate of 2400 FIT,Example of FIT Rate Calculation for an Optical Amplifier Provided by the EDFA Supplier(1),Example of FIT Rate Calculation for an Optical Amplifier Provided by the EDFA Supplier(2),Overall FIT rate:3457.7,Siemens Reliability Process Overview,Card FIT Rate,Feedback from Field Return Rate,Reference FIT Rate for electrical and mechanical components,SN 29500 developed by ZT SR Corporate Function Standardization and Regulation,Cross-functional expert team SN 29500,Committee QualityUsed by all Siemens divisionsUpdated by expert team with data from:field experience,component qualifying teams and component manufacturers,History and acceptanceDeveloped as companys internal standardFirst edition in 1978Worldwide used by the most Siemens groupsWidely used outside the companyGenerally used calculating the Siemens telecommunications systemsApproved worldwide by the customersFully in accordance with EN/IEC 61709,actually parts Part1:GeneralPart2:integrated circuitsPart3:discrete semiconductorsPart4:passive componentsPart5:electrical connectionsPart6:connectors and socketsPart7:relaysPart9:switchesPart10:signal and pilote lampsPart11:contactorsPart12:optical semiconductors,signal receiversPart13:light-emitting and infrared diodesPart14:optocoupler,FIT Rates of Individual Electrical Components,Reliability of Basic Booster(OLISTBNC):Contribution of Component Group,Reliability of Standard Booster(OLITBNC):Contribution of Component Group,Siemens Reliability Process Overview,Card FIT Rate,Feedback from Field Return Rate,FIT Rates of Individual Mechanical Components,Siemens Reliability Process Overview,Card FIT Rate,Feedback from Field Return Rate,Reliability Calculation of OLI,FIT Rates-Improvements,Calculation with respect to following conditions:80 ch load 40 deg C board temperature,*New OLI type in 3.12 will reduce FIT rate further by approx.15%,FIT decreases by additional 15%at 30 deg C(board temp.),
