The storage and shelf life of PCB circuit boards are important steps to ensure the quality and performance of the circuit boards. Here are some key information about the storage and shelf life of PCB circuit boards:
Storage conditions:
1. Temperature and humidity: PCB circuit boards should be stored in an environment with a temperature range of 22 ℃± 4 ℃ and a humidity below 70% RH. For antioxidant boards, the temperature range can be relaxed to 10-28 ℃, but the humidity also needs to be controlled below 70% RH. Meanwhile, the storage location should avoid direct sunlight and preferably be stored in a dry and ventilated warehouse.
2. Packaging requirements: Circuit boards should be vacuum packed or other moisture-proof measures should be taken during storage, such as using bubble wrap and moisture-proof beads. Bubble film can wrap around the side of the box, providing good moisture resistance. Meanwhile, packaged products should be classified and labeled for easy management and identification.
3. Storage location: PCB circuit boards should be stored in a dry and ventilated place away from the ground, and the box must be separated from the wall to avoid moisture and temperature changes affecting them.
Shelf life and precautions:
1. Unopened PCB shelf life: Under the above storage conditions, the reference period for antioxidant boards is 6 months, and it is usually recommended to use them within 3 months. The reference period for other surface treatment boards is 12 months, but it is usually recommended to use them within 6 months.
2. Shelf life of opened PCB: Under the same storage conditions, it is recommended to complete SMT work within one week after opening the PCB to avoid moisture or oxidation of the circuit board.
3. Handling of exceeding the shelf life: If the PCB circuit board exceeds the shelf life, QA review is required. Only qualified products can be shipped, while unqualified products will be scrapped.
In addition, there are some specific situations that need to be noted:
• In the PCB production process, circuit boards need to be baked at 120 degrees Celsius for at least 4 hours before SMT SMT placement, which is stored in vacuum packaging for more than 3 months.
• If the manufacturing date of the PCB board exceeds 2 months but the seal is not opened, it can be directly put online for use; If opened, it must be put online and used up within 5 days, and the date of opening must be indicated. If the deadline is exceeded, it needs to be baked at 120 ± 5 ℃ for a certain period of time before going online.
