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Can the quality of components from older date code still be used? Why is there a popular saying that the quality of components will decline when they expire, but in fact， a large number of manufacturing industries still use old components?
Especially when components are in short supply, using older components is a choice many people have to make. In other words, there are many components with old age in the electronic equipment you use now.
What application risks may occur with older components?
• If old components cannot be properly stored, moisture in the air will enter the components, causing the components to be soldered in actual application scenarios.
• The solderability is reduced, and during the high-temperature reflow soldering process, moisture evaporates inside the component, causing the component to bulge and crack. This is caused by poor storage of components and cannot prove that the quality of old components is unreliable.
Study on Solderability of Old Components
• In fact, all components are well beyond the date code range established by the manufacturer, and the chip and die life is extremely long.
• In 1998, someone specifically conducted experiments and inspections on a batch of American, aerospace-grade transistors JANS2N2219AL with a production date of 1980. This batch of components had been stored for 17 years. At that time, the inspector randomly inspected 10 tubes. The 6000h full-power life test found that the electrical parameter changed very little, which showed that long-term storage had no impact on its reliability. In 2006, when these components were 26 years old, they were re-tested, and the results were the same as those in 1998. The parameters of the year are all consistent, with almost no obvious changes. Of course, this is an aerospace-grade component.
practical experience
• In my more than 17 years of experience in the supply of electronic components, I have seen most of the components used by terminal manufacturers. The most exaggerated one was that a terminal manufacturer used components from 43 years ago. In fact, The application situation is not as bad as imagined.
• Components that are properly stored for a long time will not affect their solderability and quality. The key is whether the components can be properly stored in an environment with balanced temperature and humidity. There are also many component suppliers that have a service life of more than 10 years and properly The stored components were subjected to solderability research, and the quality of the components stored in sealed bags was not significantly different from those in the new date code.
