Early Failure
Failure patterns in newly manufactured electronic components often show a high frequency of breakdowns during the initial hours of operation. Known as infant mortality, the effect describes the portion of a population that fails due to latent defects rather than wear. Once this initial group is eliminated, the failure rate for the remaining units drops to a stable baseline.
This period represents the most volatile phase of a product’s life.
Manufacturing Defect
Material impurities or assembly errors are the primary causes of these early breakdowns. While most units in a batch are healthy, infant mortality identifies the few that contain weak solder joints or microscopic cracks. These flaws are often invisible during standard visual inspection.
Screening Effect
Stress tests like burn in are designed to trigger these latent failures within the factory. By subjecting parts to heat or voltage, the infant mortality period is compressed into a manageable timeframe. This ensures that only components in the stable middle portion of the reliability curve are shipped to the field.
Statistical Probability
Reliable systems require a predictable mean time between failures. If a batch exhibits high infant mortality, the early data points will skew the overall reliability projections. Engineers use the Weibull distribution to model these events and determine when a product has reached its stable operating phase.
