PCBA Tech - What are AOI, X-RAY and ICT in SMT industry?

SMT is the upstream industry of the electronics industry, commonly known as surface mount technology. The electronic products seen in daily life basically require SMT technology to achieve. The large or small motherboards in electronic products involve various components, and all kinds of Components are realized through SMT technology. There are many testing procedures and related equipment in the SMT industry. Today I will talk about SMT optical detectors, which are AOI, X-RAY, and ICT.

AOI

AOI is translated into Chinese into Automatic Optical Inspection, which is the abbreviation of Automated Optical Inspection. It is an equipment that detects common defects encountered in welding production based on optical principles. It uses high-speed and high-precision visual processing technology to automatically detect various stickers on PCB boards.

Assembly errors and welding defects, by using AOI as a tool to reduce defects, find and eliminate errors in the early stage of the assembly process to achieve good process control. Early detection of defects will avoid sending bad boards to the subsequent assembly stage. AOI will reduce repair costs and avoid scrapping unrepairable circuit boards.

X-RAY

X-RAY is called X-ray detector in Chinese. It has strong penetrability. Its perspective view can show the thickness, shape and mass density distribution of solder joints. This indicator can fully reflect the welding quality of solder joints, such as open circuit and short circuit., Insufficient amount of air bubbles and tin in holes and holes. There are two types: direct X-ray detector and tomographic X-ray detector. Minimum resolution/use: 50um overall defect; 10um general PCB inspection and quality control, BGA inspection; 5um fine pitch lead and solder joint inspection um-level BGA inspection, flip chip inspection, PCB defect analysis and process control; 1um bonding crack Detection, microcircuit defect detection.

ICT

ICT, commonly known as in-circuit test, performs performance tests on the wrong component polarity, wrong component type, and the value exceeds the allowable range of the nominal value. At the same time, it checks out related defects that affect its performance, including bridging., Welding, open circuit, wrong component polarity, value out of tolerance, etc., and adjust the production process in time according to the exposed problems. Contact detection technology. There are two types: manufacturing defect analyzer MDA (Manutacturing Defects Analyzer), an early form of ICT, which can only simulate and test the master board of analog circuits; the other is ICT, which can test almost all defects related to the manufacturing process, And can accurately determine defective components, mostly using central processing unit technology.

With the rapid development of electronic products, many components are getting smaller and smaller, and the density of board components is getting higher and higher. In order to ensure the reliability and stability of PCBA boards, SMT electronic processing manufacturers conduct online inspections to ensure the efficiency of customer products and product manufacturing. The application of instruments is becoming more and more lacking and becoming more and more important.