PCBA is a printed circuit board with various components welded on the surface. Many people pay attention to the reliability of its long-term and high-frequency operation, and sometimes need to know its shelf life. In general, the shelf life of PCBA is 2 to 10 years.
Factors affecting the storage of PCBA
- The environment
A humid and dusty environment is obviously not conducive to the preservation of PCBA. These factors will accelerate the oxidation and contamination of PCBA and shorten the shelf life of PCBA. In general, it is recommended to store the PCBA in a dry, dust-free space with a constant temperature of 25 degrees Celsius.
- Reliability of components
The reliability of components on different PCBAs also determines the shelf life of PCBA to a large extent. Components with high-quality materials and processes have the ability to resist harsh environments, with a wider range of capabilities and stronger anti-oxidation capabilities. Stability is guaranteed.
- The material and surface treatment process of the printed circuit board
The material of the printed circuit board itself is extremely difficult to be affected by the environment, but its surface treatment process is greatly affected by air oxidation. The surface treatment of good craftsmanship can prolong the shelf life of PCBA.
- PCBA operating load
The operating load of PCBA is the most important factor for its shelf life. The operation of high frequency and high load will have a continuous high impact on the circuit and components of the circuit board, and it is more likely to be oxidized due to the influence of heat, resulting in long-term operation. Short circuit, open circuit phenomenon occurs. Therefore, the operating parameters of the PCBA should preferably be in the middle value range of the components and avoid being near the peak value, which can effectively protect the PCBA and prolong its shelf life.
The shelf life of PCBA is a comprehensive work, and it is necessary to follow scientific design specifications, production process specifications and operation specifications, which can extend its shelf life to the greatest extent.
How to extend the storage time of PCBA
- Good storage conditions: the temperature is less than 25 degrees, the relative humidity is less than 65%, with temperature control, and the indoor environment is free of corrosive gases.
- General storage conditions: the temperature is not higher than 35 degrees, the relative humidity is less than 75%, and the indoor environment is free of corrosive gases.
The temperature of the warehouse where PCBA is stored is best controlled at 23±3℃, 55±10%RH. Under such conditions, PCBA with surface treatment such as immersion gold, electro-gold, spray tin, silver plating can generally be stored for 6 months. PCBA with surface treatment such as silver, immersion tin, OSP can generally be stored for 3 months.
For PCBA that has not been used for a long time, it is best for the circuit board manufacturer to paint a layer of three-proof paint on it. The function of the three-proof paint can prevent moisture, dust and oxidation. This will increase the PCBA shelf life to 9 months.