Question

describe HALT and HASS testing. what is the major difference between them ?

Answer 1

HALT - Highly Accelerated Life Test

HASS - Highly Accelerated Stress Screen

HALT & HASS are special, rapid test methods for product quality focused on finding product flaws so that they can be corrected before becoming costly field problems. Different since HALT and HASS vary from conventional testing of model validation-different objectives, different pressures, different results.

Accelerated, because in a matter of hours or days, HALT and HASS expose modes of product failure compared to traditional test methods that can take weeks or even months to identify, if any.

HALT and HASS, collectively referred to as Accelerated Stress Testing (AST), expose a material to a series of overloads, effectively forcing poor product connections to emerge from accelerated fatigue. Unlike traditional single-axis vibration testing methods or thermal-only methods, an AST program requires specialized HALT / HASS equipment to render the required stresses repeated six-degree vibration and rapid thermal change rates in the combined environment required to drive out latent failure modes.

Stresses are applied in a guided, gradual fashion in HALT and HASS while the system under test is monitored continuously for failures. Once the product's limitations have been established and corrective actions taken, the product's boundaries are clearly understood and the profit margins have been expanded as far as possible. With a higher degree of reliability, a much more mature product can be launched much quicker. Unlike DVT (Design Verification Testing), HALT's aim is to evaluate a design's operating and destroying limits–why those limitations exist and what is required to increase those margins. Therefore, HALT emphasizes goods outside their specific design

HALT gives engineers the opportunity to improve product design, strengthen its robustness and reduce the risk of costly warranty programs and expensive post release product recalls.