Paper title
Automated optical inspection (AOI)
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- 2.1.6. Automated X-Ray inspection (AXI)
- 2. 2. Functional tests (FT)
2.1.5. Automated optical inspection (AOI)AOI is a form of automated control and is widely used in many manufacturing areas. AOI provides very high level of discovering various solder defects, misplaced components, wrong parts or parts with wrong orientation and other visible defects. 2.1.6. Automated X-Ray inspection (AXI)AXI is very similar to AOI, but works in the invisible spectrum using X-rays. The introduction of the BGA packaging called for finding a way to control optically inaccessible objects and AXI provides it. Fig. 2. Typical structural test station 2. 2. Functional tests (FT)FT are usually performed after the product is fully assembled. Typically they emulate or simulate the real work of the device at various environment conditions. The purpose is to verify the functionality of the final product. 2.2.1. Reliability tests- Accelerated Test. The purpose of this test is to artificially induce defects in lab environment by testing the product at stress conditions at the edge or slightly over the normal work parameters. а) Highly Accelerated Life Testing (HALT) has four variations. Initially the tests are performed with temperature and step vibration load. The purpose of these tests is to find work tolerance (limits). They reveal the qualities of the product as a cyclic step change of environment variables such as temperature, shock and vibration. b) Highly Accelerated Stress Screening (HASS) is another form of HALT. HASS is a constant product screening of the regular production. At this test the product is not tested to fail but rather for proper working at successively changing environment parameters. c) Highly Accelerated Test Auditing (HASA). For high volume production where with volume increase the number of defects decrease is used HASS audit. The key parameters are monitored constantly on product samples and this way provide information on the process quality and stability. - Reliability Demonstration Test (RDT).RDT is a process for product reli- ability demonstration. It is used for determining the product readiness to be released to the market as well as its life span without work defects. - On-Going Reliability Testing) (ORT) is ongoing test on samples of regular production units used for monitoring for tendencies of reliability change during the manufacturing process. Изтегляне 79.5 Kb. Сподели с приятели:
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