SRC Forum - Message Replies
Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and Answers
Topic Posted by: Reliability & Maintainability Forum
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Posted by: Michelle Li
Date posted: Fri Nov 15 14:53:07 US/Eastern 2002
Subject: possible missleading of 217 on chip ceramic capacitors
I am working on reliability prediction for a commercial avionics flight display. I found that surface mount ceramic capacitor failure rate is about 35% of total failure rate of all elelctronic assemblies ( exclude LCD assembly and lamp assembly) by using 217. I actually did not choose 'Chip Ceramic' subcatogory, I chose 'general purpose, ceramic capacitors'. If I used 'chip, ceramic', the total failure rate of chip ceramic capacitor will go to 50%.
If I just use PRISM for surface mount ceramic capacitors and still use 217 for other parts, the ratio will drop to 5%.
Can someone tell me if surface mount ceramic capacitors cause about 35% of failures in field? It is hard for me to believe so. I guess that they might cause 1% to 5% of failures in field.
If someone works on commercial avionics field reliability, I would appreciate if you can give some information about field performance of the surface mount ceramic capacitors.
Thank you very much.
Reply Posted by: Rob Poltz
Organization: Design Analytx International
Date Posted: Wed Nov 20 16:47:58 US/Eastern 2002
I ran across this link for capacitors using the Arrhenius equation, and can be used to compare the same variables of one type capacitor on another, i.e., same temp, stress, etc.
Thought it might help answer your questions: