2 HALT Objections
Abstract
Kirk and Fred discuss the value of HALT for a product late in a new product development process.
Key Points
Join Kirk and Fred as they discuss whether applying HALT yields a good ROI (return on investment) when they are already working on reliability problems discovered during standard development.
Topics include:
- HALT is most effective when a new products electronic and mechanical subsystems can be tested separately, particularly when there are material thermal limitations from mechanical systems.
- It is very important to know the material properties of the systems under test. Usually, when a HALT limit is reached due to a change in material state, such as solder reflow or plastic melting, it is an irrelevant failure mode and a fundamental limit of technology.
- The question of when to perform HALT in development is a very important judgment to make. The system should be nearing the final form factor, with most failure modes addressed, and 80 to 90 percent operational. Before that, for purchased subsystems, such as power supplies, HALT can be used to identify the most robust design among multiple sources.
- Multi-physics CAD software has progressed and can provide some stress-related issues from its modeling, but it has to assume that the system is built with little variation in the supply chain.
Enjoy an episode of Speaking of Reliability. Where you can join friends as they discuss reliability topics. Join us as we discuss topics ranging from design-for-reliability techniques to field data analysis approaches.
Show Notes
Please click on this link to access a relatively new analysis of traditional reliability prediction methods article from the US ARMY and CALCE titled “Reliability Prediction – Continued Reliance on a Misleading Approach”. It is in the public domain, so please feel free to distribute it. Attempting to predict reliability is a misleading and costly approach to use for developing a reliable system.
If you would like to learn more about using HALT (Highly Accelerated Limit Tests) and HASS (Highly Accelerated Stress Screens), please follow this link to the book “Next Generation HALT and HASS: Robust design of Electronics and Systems,” written by Kirk Gray and John Paschkewitz. It can also be found on Amazon Books at this link.
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