QLF08_LaBel.pdf - 第10页
IC and Component Selection for Space Sy stems – Presented by Kenneth A . LaBel 10 An Example “Ad hoc” Battle • Mission requirement: High resolution image – Flowdown requirement: 14-bit 100 Msps ADC • Usually more detaile…
IC and Component Selection for Space Systems – Presented by Kenneth A. LaBel
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Risk Requirements
• Rationale
– Trying to ensure mission parameters such as reliability,
availability, operate-through, and lifetime are met
• Personnel involved
– Radiation engineer, reliability engineer, parts engineer
• Usual method of requirements
– Flowdown from mission requirements for parameter space
• I.e., SEU rate for system derived from system availability specification
• Buzzwords
– Lifetime, total dose, single events, device screening, “waivers”
• Limiting factors
– Management normally makes “acceptable” risk decision
IC and Component Selection for Space Systems – Presented by Kenneth A. LaBel
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An Example “Ad hoc” Battle
• Mission requirement: High resolution image
– Flowdown requirement: 14-bit 100 Msps ADC
• Usually more detailed requirements are used such as
ENOB or INL or DNL as well
– Designer
• Searches for available radiation hardened ADCs that
meet the above requirements
• Searches for commercial alternatives that could be
upscreened
– Manager
• Trades the cost of buying Mil-Aero part requiring less
aftermarket testing than a purely commercial IC
• Worries over delivery and test schedule of the candidate
devices
– Radiation/Parts Engineer
• Evaluates existing device data to determine reliability
performance and additional test cost and schedule
• The best device? Depends on mission priorities
IC and Component Selection for Space Systems – Presented by Kenneth A. LaBel
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Traditional Risk Matrix
Risk Tolerance Boundary
Placed on the profile to reflect
Corporate “Risk Appetite”
Caution Zone
Risks in the “yellow” area
need constant vigilance
and regular audit
By adjust the level of
currency hedging, resources
can be released to help fund
improvements to protection of
the production facility.
Likelihood Scale: A: Very High B: High C: Occasional D: Low E: Very Low F: Almost Impossible
Impact Scale: I: Catastrophic II: Critical III: Significant IV: Marginal