Forum: Reliability & Maintainability Questions and Answers
Posted by: Sheila Prather (email@example.com )
Organization:Northrop Grumman Corporation
Date posted: Wed May 17 13:49:02 US/Eastern 2000
Subject: Derating of Industrial/Commercial ICs in Plastic Packages
I reviewed the recent "Reliability Toolkit: Commercial Practices Edition" and although Table 5.1.3-1 does not specifically state that the derating information provided pertains to hermetic/ceramic packages, I assume this to be true.
In light of my assumption, would like your recommendations regarding the derating levels you feel appropriate for both silicon and GaAs MMIC ICs in plastic packages. Would like both the case and junctions temperature guidelines, as appropriate (but, at a minimum the junction temperature derating level). Thanks for your response.
Posted by: Floyd Kreuze
Date posted: Tue May 16 11:31:37 US/Eastern 2000
Subject: Lamp Accelerated Testing
I have a question about accelerated life testing of incandescent lamps. Using failure data points from testing at an accelerated (higher than normal use) voltage level, if a Weibull plot were used to determine mean life (with both failures and suspensions), what would be a good average recommended exponent (acceleration factor for lamps) when the Inverse Power Law is used to determine mean life at normal use voltage.
Posted by: Juan Moreno (firstname.lastname@example.org )
Organization:University of Valencia (Spain)
Date posted: Tue May 16 10:07:42 US/Eastern 2000
Subject: Arrhemius Acceleration Factor
I would like to know How Bellcore Isssue 6 takes the Arrhenius Factor that is applied for the units or equipment level, thanks.
Posted by: Clay Davis
Date posted: Thu May 11 14:03:05 US/Eastern 2000
Subject: Thermal Rating and Power
Do you know the relationship between the BTU/hr thermal rating and the specified power rating? Currently, the information states 610 BTU/hr, with a power rating of 125W. Generally, a power supply if this rating would yield BTU/hr of about 375 BTU/hr. Can someone verify this?
Posted by: Bob Valerius (email@example.com )
Organization:Northrop-Grumman Oceanic Systems
Date posted: Tue May 9 13:17:46 US/Eastern 2000
Subject: One Shot Device Reliability
What kind of analysis is reasonable to ask a vendor to supply to support a Probability of Success Requirement (>0.99999) for a one shot device? Thanks in advance!