1、Lessons Learned Entry: 1879Lesson Info:a71 Lesson Number: 1879a71 Lesson Date: 2008-07-14a71 Submitting Organization: JPLa71 Submitted by: David Oberhettingera71 POC Name: Linda Facto, Jeanette Plantea71 POC Email: Linda.J.Factojpl.nasa.gova71 POC Phone: 818-354-2195 (L. Facto), 301-614-5944 (J. Pla
2、nte)Subject: Guidance for NASA Selection avoid simply derating the device as a “black box.“ 8. Perform Worst Case Analysis (WCA) on DC-DC converters, analyzing not only the total radiation dose but also the enhanced low dose rate and displacement damage effects. 9. Review changes to the design or to
3、 vendor processes that occur after the device is flight qualified, and request an updated analysis or requalification if needed. 10. Verify product data sheet claims regarding device radiation hardness by analysis or test.Device Quality 11. Assure that a customer precap visual inspection is performe
4、d by a properly trained device Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-inspector as these frequently identify defects requiring rework. 12. Perform customer DPA on all non-Class K device lots because some defects occur after device lid sealin
5、g and screening.Device Procurement 13. Selection of a device vendor on the Qualified Manufacturers List is strongly recommended to achieve device quality 14. Because MIL-PRF-38534 has deficiencies even for Class K devices, employ a statement of work (SOW) or source control drawing (SCD) to add custo
6、mer precap visual inspection, capacitor and Schottky diode screening, and periodic MIL-PRF-38534 Group C (especially life test) testing. 15. Plan for converter procurement as long lead time (i.e., greater than 6-month) items because the desired converter will not typically be available from vendor i
7、nventory. 16. Seek to procure high quality devices. The total cost of lower quality, including upscreening and the cost and schedule impact of lot failures on the project, may greatly exceed the initial cost of the higher quality devices. 17. It is vital that the project plan and budget for a monito
8、ring team representing the design engineering, electronic parts engineering, quality assurance engineering, and reliability engineering functions throughout the procurement cycle to resolve issues related to device application or lot failures. Evidence of Recurrence Control Effectiveness: JPL has re
9、ferenced this lesson learned as additional rationale and guidance supporting Paragraph 7.5.4 (“Safety and Mission Assurance Practices: Electronic Parts Reliability, Application, and Acquisition“) in the Jet Propulsion Laboratory standard “Flight Project Practices, Rev. 6,“ JPL DocID 58032, March 6,
10、2006. In addition, JPL has referenced it supporting Paragraph 4.12.4.1 (“Flight Electronics Hardware System Design: Analog Design Power Converter Synchronization“) in the JPL standard “Design, Verification/Validation and Operations Principles for Flight Systems (Design Principles),“ JPL Document D-1
11、7868, Rev. 3, December 11, 2006. Documents Related to Lesson: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Mission Directorate(s): a71 Sciencea71 Exploration SystemsAdditional Key Phrase(s): a71 Program Management.a71 Program Management.Acquisi
12、tion / procurement strategy and planninga71 Missions and Systems Requirements Definition.a71 Missions and Systems Requirements Definition.Review boardsa71 Systems Engineering and Analysis.a71 Systems Engineering and Analysis.Engineering design and project processes and standardsa71 Systems Engineeri
13、ng and Analysis.Long term sustainability and maintenance planninga71 Systems Engineering and Analysis.Mission and systems trade studiesa71 Engineering Design (Phase C/D).a71 Engineering Design (Phase C/D).Powera71 Engineering Design (Phase C/D).Spacecraft and Spacecraft Instrumentsa71 Manufacturing
14、and Assemblya71 Integration and Testinga71 Safety and Mission Assurance.a71 Safety and Mission Assurance.Early requirements and standards definitiona71 Safety and Mission Assurance.Product Assurancea71 Safety and Mission Assurance.Qualitya71 Safety and Mission Assurance.Reliabilitya71 Safety and Mis
15、sion Assurance.Review systems and boardsa71 Additional Categories.a71 Additional Categories.Flight Equipmenta71 Additional Categories.Hardwarea71 Additional Categories.Industrial Operationsa71 Additional Categories.Payloadsa71 Additional Categories.Risk Management/Assessmenta71 Additional Categories
16、.SpacecraftAdditional Info: a71 Project: variousProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Approval Info: a71 Approval Date: 2008-09-17a71 Approval Name: mbella71 Approval Organization: HQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
