LED indicators are one of the most commonly sold and used components in electronics. These components are integral to HMI systems and ensuring that users understand what their equipment is doing, often meaning assemblers keep stocks on hand for repairs or rapid assembly. We’ve had some questions recently concerning product expiry for these devices - do LEDs expire, and if so after how long?
LEDs themselves are well-sealed solid-state components. They do not generally expire. The metallized leads used to solder them to a board, however, do suffer the effects of aging. They don’t ‘expire’ as such, but as with virtually all electronic products with solder leads, those leads can experience oxidation over time. This oxidation can reduce the leads’ solderability and cause unexpected gremlins in finished products if not accounted for. As a general rule of thumb, many suppliers recommend performing solderability tests on components that have been stored unused for more than two years.
Again, this does not mean the product has “expired” and is unusable. It means the product’s solderability might have been reduced, and special steps will be required to try and make use of it if so.
Proper storage of these components can slow this process, and manufacturer reels for these devices is often designed to minimize this aging as well. Nothing can stop it, but proper storage combined with solderability tests for older products can minimize the impact on your products from aging of older products.