Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and AnswersTopic Posted by: Reliability & Maintainability Forum (firstname.lastname@example.org )
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Original Message:Posted by: Godder Shao (Godder.email@example.com )
Organization:System General Corp.
Date posted: Wed Dec 22 22:47:07 US/Eastern 2004
Subject: How to calculate MTTF for Temperature/Humidity bias life
I have one product(Power IC) need to perform temperature/humidity bias lift test(THB). I follow JEDEC-22 A110 standard to perform it, and test condition as below, 85 degree C/85% R.H./VDD=20V 1000hrs 30pcs. after this test was finished, the test result as below, 22pcs failed at 768hrs, 6pcs failes at 928hrs, 2pcs failed at 1000hrs. could you teach me how to calculate the MTTF at 30 degree C/60% R.H./VDD=20V ? Thanks!