Sitting Bare Shelf Life of the Main Three Categories of Printed Circuit Board
Circuit boards use tracks, rivets, and pads to draw subtle electronic signals across the board. These slight signals will force some end result. This is usually a computational response. They are the engineered building blocks of just about all electronic equipment. For better or worse, they have a shelf life. Consumers often ask how long a specific printed circuit board has been sitting in manufacturing before being shipped out and sold. The answer could vary from one week to a full year. Interestingly, printed circuitry has a manufacturing shelf life. Consider this the “sell by” date that manufacturers use to determine if a board is viable in the consumer marketplace. Retailers and even second-generation manufacturers rely on these numbers and assurances from the manufacturer.
When speaking of shelf life, the determination is usually bare. This means that the circuit boards are exposed to dust and other obstacles. Bare also means that they have not been fully laminated and smoldered. There are three categories, aptly titled one, two and three, and different categories boast different shelf spans. The main difference between each one is the thickness and build of the board.
These circuit boards need to be smoldered within 30 days. After that, they need to be re-baked or tossed away entirely.
The second category of circuit boards are generally okay being bare for about 6 months. They can sit awaiting smoldering for this period of time without losing quality.
The final main category of circuit boards has a shelf life between 6 months to two years. Some boards can last longer, but they are specialty items (and rare for printed boards).
The circuit boards get old because they accumulate moisture and air debris. The moisture is the biggest threat. They can also split in a process called delamination. Baking ultimately destroys the board’s solderability. This means that once baked, it cannot be shelved for very long. In development, boards are stored in a safe and dry environment. It could take up to a year or two for boards to finalize to completion. Until then, they are held safely and responsibly.