Forum: Reliability & Maintainability Questions and Answers
Posted by: Phil Friedel
Date posted: Fri Feb 8 18:22:33 US/Eastern 2002
Subject: Reliability and Maintainability Corrosion report
I'm trying to find a report that I once had written by the head of Reliability and Maintainability within DoD the subject of which was corrosion prevention. I believe it was related primarily to avionics. I think it was an SP- report. Now I can't find a trace of the report and I can't remember the name of the dept head who authored it. Any clues on how to find the report number or author?
Posted by: D. Fazioli (email@example.com )
Date posted: Tue Feb 5 10:25:04 US/Eastern 2002
Subject: Traditional ESS IAW NAVMAP
Is 2 recorded failures which occurred after cycle 5 justification to reduce the ESS tempature cycles from 10 to 5? This failure data is based upon a review of ESS data with respect to 200 WRAs tested over the last 6 months. These WRAs are ultimately used in a military fighter inhabited environment. For the same 200 WRAs, the number of failures recorded was 120 before completing the 5th ESS tempature cycle. We want to reduce cycle time but not at the risk of jeopardizing reliability of the WRAs. Is this adequate data to convince the customer to reduce the number of cycles to 5 in lieu of 10 temperature cycles?
Posted by: Richard Smith (firstname.lastname@example.org )
Date posted: Wed Jan 30 9:25:44 US/Eastern 2002
Subject: RDGT Testing
I have a question regarding RDGT testing for similar products. For example, if we have three similarly designed products that only vary with the number of installed circuit cards (internally in a rack for example), is it possible to only run one type through RDGT and then form conclusions on the reliability of the other two.
If this is a valid process, which product would be the best one to evaluate ? The low, medium or high complexity product ? (my thinking is the high comlexity, but for cost reasons the medium may be the best). Any comments appreciated.
Posted by: Keith Heinzig (email@example.com )
Organization:Solus Micro Tech.
Date posted: Mon Jan 28 19:58:04 US/Eastern 2002
Subject: NTC Thermistor Reliability
I am trying to locate reliability data on NTC thermistors running above 70 degrees C for extended periods. If anyone could point me to a source of data I would appreciate it.
Posted by: Sadat Hussain (firstname.lastname@example.org )
Date posted: Mon Jan 28 16:32:48 US/Eastern 2002
Subject: ASIC Reliability
Are there any generic guidelines for ASIC reliability?
-Useful Life? -Average failure rate Things I don't know but want to find out: - Number of machine on/off cycles = ??? - Number of Machine Mini-cycles = ??? - Mini cycle duration = ??? * A mini-cycle is defined as a significant deviation from normal power on operation. From what a vendor tells me, this is the number of "unusual" power up cycles and the info is used for second level attach reliability analysis Can someone please provide me some typical values for the above parameters??