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 lists component rating by design new & critical components specification new components & supplier audits,in production failure control field return analysis & threshold monitoring conservative data based on predicted values regular component supplier audits,Reliability Control and Improvement,Cross-functional team established to install focused program Close interaction with the supplier for design, technology and process Early failure monitoring and feedback in development phase Extended testing including temperature cycling in production Detailed 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 FMA non-installed equipment at certain carriers low channel count for many years temperature for FIT estimation probably higher than in reality margin (e.g., due to low channel count, low PMD, BOL) can mask performance degradation,Functional Partition of OLI,Optical amplification via EDFA gain block Pump diodes Monitor diodes EDF-Heater Internal Gain Switch OSC splitting functions as Add / Drop of the OSC channel using wavelength selective couplers Splitting of monitor signals at the input and output port and at intermediate measurement points Spectral shaping of the signal using a VOA for setting the EDFA to an optimized operating point GTC for tilt compensation Optical monitor ports at input and output for signal supervision APSD circuitry Gain Control and Supervision (DSP, on-board processor) Electrical components for control and power supply Mechanics 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 Reliability Reference conditions for failure rates and stress models for conversion (no basic failure rates),Relationship between Standards SIEMENS standard SN29500 / IEC 61709 compared to SR-332,SR-332: Reliability Prediction Procedure for Electronic Equipment,SN29500: Failure rates of components Expected values (This is in addition to IEC 61709),a) Climatic and mechanical stresses per IEC 721-3-3 (see next slide) multiplying factors for environmental conditions b) Quality factor tested components SN72500 4 quality levels known c) Temperature and electrical stress by reference conditions IEC 61709 given 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 fully correspond with the already existing SIEMENS standard SN 29500 method.,Details: SIEMENS Standard SN29500 and IEC 61709,FIT Rates of Individual Electrical Components (1),Voltage dependence and Current dependence,U Operating voltage in V Uref Reference voltage in V Umax Rated voltage in V C1 Constant in (1/V)C2 C2,C3 Constants (1).Digital CMOS Families, Contactors (2).Others,I Operating current in A Iref Reference current in A Imax Rated current in A C4,C5 Constants,FIT Rates of Individual Electrical Components (2),A Constant Ea1,Ea2 Activation energies in eV TU,ref Reference ambient temperature in K T1 Reference junction*)- (comp.*)-) temperature in K T2 Actual 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 calculated by 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 vendor What 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 estimate FIT 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 place Estimates by two vendors: 3500 - 4800 FIT Reduction to 5000 FIT beginning of 2004 Quality improvement discussions with the vendors ongoing Check with field returns: 1600 FIT Reduction to 4000 FIT(Siemens estimate) in April of 2004 Continuously monitored Similar 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 Quality Used by all Siemens divisions Updated by expert team with data from: field experience, component qualifying teams and component manufacturers,History and acceptance Developed as companys internal standard First edition in 1978 Worldwide used by the most Siemens groups Widely used outside the company Generally used calculating the Siemens telecommunications systems Approved worldwide by the customers Fully in accordance with EN/IEC 61709,actually parts Part 1: General Part 2: integrated circuits Part 3: discrete semiconductors Part 4: passive components Part 5: electrical connections Part 6: connectors and sockets Part 7: relays Part 9: switches Part 10: signal and pilote lamps Part 11: contactors Part 12: optical semiconductors, signal