Clarifying a Point About HALT
Abstract
Kirk and Fred discuss the continued meaning of the acronym HALT, which was originally coined by Gregg Hobbs, Ph.D., P.E., to stand for Highly Accelerated Life Test, which is a misnomer.
Key Points
Join Kirk and Fred as they discuss a listener’s question about the use of the term HALT and what its purpose is.
Topics include:
- During the many years Kirk worked with Gregg Hobbs, he discussed with Gregg, along with others, how the term “life test” would be misunderstood as a quantitative test that would give an estimate of field life.
- HALT should be understood as a discovery test, a discovery of weaknesses in the design, and a discovery of strength distributions between samples.
- HALT should be considered as a Highly Accelerated Limit Test, and the endpoint of how close the strength capability of a test sample is to the fundamental limit of the technology. That is the point at which the system strength cannot be increased with standard materials and components.
- From the perspective of HALT, the more strength margin you have in a product beyond the required strength, the higher the probability of being reliable throughout its useful life. Often, a new design is already at the fundamental limit of the technology, and no changes are needed.
- Quantitative “Life Test” can be performed for a single component or mechanism, but at the system level it is very difficult to account for all the variations in the materials, manufacturing and end use to declare any test as an accelerated life test.
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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