文档介绍：INTRODUCTION
Purpose
This document is the worldwide test and reliability standard used to specify accelerated stress testing (AST) of electrical and electronic products.
Overview
Background information, methodology, responsibilities, and detailed procedures for AST are contained in this document. AST consists of highly accelerated life test (HALT), screen verification, proof-of-screen (POS), and highly accelerated stress screening (HASS).
Definitions & Acronyms
AST = accelerated stress testing
HALT = highly accelerated life test
HASS = highly accelerated stress screening
POS = proof-of-screen
UOTL = upper operating temperature limit
LOTL = lower operating temperature limit
UDTL = upper destruction temperature limit
LDTL = lower destruction temperature limit
OVL = operating vibration limit
DVL = destruction vibration limit
BACKGROUND
Purpose
The purpose of AST is to precipitate and detect (observe) defects in products during design and detect defects during manufacturing. Relevant defects, or those likely to occur in deployment, must have the root cause identified and the optimal solution must be determined, implemented, and verified. Section contains more information on relevant defects.
Methodology
During AST, applied stresses will be increased above expected deployment levels pensate for a relatively small sample size and to find defects quickly.
AST simulates the decrease in product strength over time (cumulative fatigue damage) or an absolute overstress condition.
AST uses a “test-to-failure” methodology during product design and a “screening” process during manufacturing. These are defined in more detail in sections 4 to 6 of this document.
The accelerated stress test methods for electronics and electrical products include:
1. HALT (or product ruggedization)
2. Screen verification and POS (preparation for HASS),
3. HASS
These methods can also be applied to some electromechanical products.
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