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Application Examples for ALTA

ReliaSoft's ALTA accelerated life testing data software provides an extensive array of tools to help you understand and communicate how a product will perform over time. Some of the many useful applications include the ability to:

•Understand and quantify the effects of stress (or other factors) on product life.

•Design accelerated tests that will be the most effective to achieve desired objectives.

•Significantly reduce the test time required to obtain reliability metrics for a product, which can result in faster time-to-market, lower product development costs and improved designs.

We have compiled some case studies to demonstrate the types of analyses that you will be able to perform with ALTA. For the actual case studies, the data and/or exact test method that were used may have been modified in cases where the actual information was deemed to be confidential.

Example 1:

Voltage Step-Stress

An electronic component is subjected to a voltage stress, in stepwise increments. The objective of this study is to determine the B(10) life and the mean life (often called "mean time to failure," MTTF or MTBF) of these components at the normal use stress level.

See Example

Example 2:

Accelerated Demonstration Test An electronic component is put on an accelerated test using three different (constant) temperature stress levels with the objective of demonstrating B(10) life with a specified confidence level. In this study, the activation energy and acceleration factors are also computed.

See Example

Example 3:

Accelerated Degradation Analysis A chemical solution (e.g., ink formulation, medicine, etc.) that degrades with time is studied. A quantitative measure of the quality of the product is utilized and that measure is tracked through an accelerated degradation scheme over time to determine the shelf life of the product. The product is considered failed (or out of compliance) if that quantitative measure falls below a certain value. In this study, although none of the specimens fail, data concerning their degradation is utilized for subsequent analysis.

See Example

Example 4:

Automotive Part Test Multiple stresses are applied simultaneously to a particular automotive part in a step-stress method. In this scenario, the stresses are quantified in terms of a "percentage stress" as compared to typical stress levels (or assumed field conditions). The test objective is to estimate the B(1) life for the part (i.e., time at which reliability is equal to 99%) at the typical operating conditions (i.e., Stress=100%), in miles.

See Example

Example 5:

Using Indicator Variables A sample of electronic components are subjected to a quantitative accelerated life test in which three stress types are applied to the units. The stress types include temperature, voltage and a third indicator variable to describe whether the units are operated continuously or turned on and off. The general log-linear model is used to analyze the data set for this test.

See Example

Example 6:

Stability / Shelf Life Study A consumer product (e.g., a mouthwash, shampoo, etc.) is made up of three main ingredients (ingredients A, B and C), that have a characteristic (e.g., concentration) that may or may not change with time. This example looks at data obtained during a 12 month test period to predict the percent out of compliance after 24 months, as well as the behavior of each characteristic over time.

See Example

Example 7:

Accelerated Life Test Plans A reliability group in a semiconductor company is planning an accelerated test for an electronic device. This example demonstrates how to plan such a test using ALTA's Accelerated Life Test Plans utility.

See Example

Example 8:

Multiple Time-Varying Stresses The cumulative damage model allows you to analyze accelerated life testing data with up to eight time-varying stresses. In this example, we consider such a case and look at how to create stress profiles in which stress is a function of time.

See Example