conference & convention enabling the next generation of networks & services Reliability Performance of TE SubCom’s Generation-3 DPSK HPOE Generation-3 DPSK HPOE Barbara Dean and Charles Breverman Tyco Electronics Subsea Communications
conference & convention enabling the next generation of networks & services Presenter Profile Barbara joined Bell Laboratories after receiving her Ph. D. in Chemical Physics from Ohio State University. She has contributed to the development and reliability analysis of optical transmitters, Place receivers and passive components for both terrestrial picture and undersea applications. Her engineering team was here responsible for the qualification and certification responsible for the qualification and certification strategy for undersea pump lasers. Barbara later joined the undersea system division (now TE SubCom) and is currently responsible for Quality Management implementation and Reliability Management and assessment. Barbara Dean Managing Director Email: bdean@subcom.com Tel: (+1) 732 578 7874 Mobile Tel: (+1) 732 856 4511
conference & convention enabling the next generation of networks & services Outline • Introduction • Architecture of HPOE • Initial Estimate of Reliability • Risk Issues in Design and Start of Manufacture • Risk Issues in Design and Start of Manufacture • Field Experience • Conclusions
conference & convention enabling the next generation of networks & services Introduction � The final capacity per Digital Line Segment in undersea communication systems has roughly doubled in the past five years. � One consequence of the increased capacity is the possibility of over 100 transmit/receivers (High possibility of over 100 transmit/receivers (High Performance Optical Equipment or HPOE) per line-pair in a station. � Management of reliability is crucial to prevent excess costs due to outage mitigation, sparing and station staffing.
conference & convention enabling the next generation of networks & services Subcom’s Gen-3 HPOE • Single circuit pack providing bidirectional transmission • Occupies a single slot in • Occupies a single slot in the Common Shelf • Enhanced FEC • Wavelength tunable transmission laser • RZ-DPSK format
conference & convention enabling the next generation of networks & services Key Considerations � Where possible, choose parts from suppliers with a proven record of excellent reliability in both terminal and submerged equipment. Push these suppliers to meet performance specifications, rather than immediately opting for an unproven rather than immediately opting for an unproven supplier that claims to meet the specification. � Take advantage of improvements in monolithic integration, with more of the required functionality executed in fewer ICs. � Eliminate adhesives in the optical path – especially important for new entrants.
conference & convention enabling the next generation of networks & services Types of Components for Each Functionality • XFP Module Client Interface • Serializer/Deserializer Increased • FEC Processor FEC Processing FEC Processing Integration Integration • Oscillators • Logic IC Line Transmitter • Tunable Laser • Modulator
conference & convention enabling the next generation of networks & services Types of Components for Each Functionality • Logic IC Line Receiver High • PIN-TIA Reliability • DPSK Demodulator Suppliers • Optical Amplifiers • Optical Amplifiers Other • Optical Jumpers • Discrete Components • Firmware • PWB / EMS
conference & convention enabling the next generation of networks & services Initial Estimate of Component Failure Rate • Considered the failure rate estimated from Telcordia aging tests – These estimates are likely to be very conservative due to limited sample size • Considered failure rates based on field • Considered failure rates based on field experience of similar parts from same wafer fab and packaging house – Must understand if parts are likely to be returned upon failure and the FMA capability of the supplier • SubCom’s experience with similar parts and technology
conference & convention enabling the next generation of networks & services Early Estimate of HPOE Reliability Module Functionality FITs @90% c.l., 65 ° ° C ° ° Client Interface 2,100 FEC Processing 690 Line Transmitter 3,080 Line Receiver 5,150 Optical Amplifiers 4,550 Optical Jumpers 450 PWB, passive electrical components, firmware 3,000 Estimated Total FITs ~19,000
conference & convention enabling the next generation of networks & services Risk Issues in Design and Start of Manufacture � Typical issue – migration of IC package from ceramic to plastic occurred during Models phase causing qualification approval of component to be simultaneous with start of production simultaneous with start of production � Atypical issue – discovery of counterfeit parts
conference & convention enabling the next generation of networks & services Types of Counterfeit Parts � Dummy packages � Parts with labeling that misrepresent the part’s form, fit, function or origin (including Pb-free solder) � Parts that are labeled as having undergone � Parts that are labeled as having undergone additional reliability screening, but have not � Parts rejected by the manufacturer’s test and inspection process � Used parts represented as new
conference & convention enabling the next generation of networks & services Counterfeit Parts Encountered � Very high in-process failure rate of a chip capacitor – Suspect used part sold as new � A few in-process failures of an IC from a respected supplier – Request for FMA led to discovery that the Serial Number – Request for FMA led to discovery that the Serial Number was bogus – Suspect relabeled or purpose-built counterfeit part � World-wide supply of the true part was very much smaller than assumed, leading to a potential schedule risk � Flash memory chip query returned the information that the chip was from Supplier A – Package labeled as Supplier B – Purpose built counterfeit part
conference & convention enabling the next generation of networks & services Countering Counterfeit Parts � Treat as Intellectual Property theft and inform the victimized supplier and any counterfeit data repositories � Purchase from Authorized Distributors or from Distributors open to audits and supplying life Distributors open to audits and supplying life traceability of the part � Use EMS with a Counterfeit Part plan and ability to test subtle features � All countermeasures put in place before start of manufacture
conference & convention enabling the next generation of networks & services Field Experience Number of Deployed Active HPOEs 3000 • the number of active HPOEs deployed in systems or 2500 upgrades that have 2000 completed the acceptance HPOEs # Active HP process process 1500 00 1000 500 0 12/31/2006 12/31/2007 12/31/2008 12/31/2009 Dec ‘09 Dec ‘07 Dec ‘08 Dec ‘06 Time
conference & convention enabling the next generation of networks & services Distribution of Size of HPOE Installations • “Installation” - the number of 20 active HPOEs ordered for a network build or upgrade 15 llations • The most frequent installation size is N ~24 installation size is N ~24 # Installat 10 • Uncertainty associated with a confidence that the failure 5 rate of a given installation is the same as predicted 0 1 / scales as N 0 100 200 300 400 500 600 # HPOEs per Installation
conference & convention enabling the next generation of networks & services Evolution of Return Rate with Time • The Estimated Time Evolution of HPOE Return Rate Return Rate is the 20000 Component-Based Failure Estimate point estimate turn Rate (FITs) – Ratio of total 15000 number of returns to Estimated Retur total active HPOEs total active HPOEs 10000 deployed at the end 5000 of the time period – No “confidence 0 level” attached – 12/31/2006 12/31/2007 12/31/2008 12/31/2009 Dec ‘08 Dec ‘09 Dec ‘06 Dec ‘07 represents what the Time systems actually experienced
conference & convention enabling the next generation of networks & services Observations on Return Rate � At all times, the population return rate is lower than the original conservative estimate � There is a peak after the first year of deployment followed by a steady decrease � Increase in population size will make the estimate � Increase in population size will make the estimate more robust, but not by itself lead to the observed decrease � Is a very low return rate for newer installations masking continued higher return rate for earlier installations?
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