The reliability testing of PCB boards is a complex and rigorous process, covering multiple aspects such as soldering quality, functionality, environmental adaptability, and specialized testing. By selecting testing items and standards reasonably and applying and executing them according to the correct process, the quality and performance of PCB boards can be ensured to meet the highest standards.
1、 Welding quality and appearance inspection
AOI testing uses advanced cameras and image processing software to conduct a comprehensive inspection of the soldered PCB board. It can accurately capture the position, polarity, and welding quality of welded components, effectively detecting common defects such as solder short circuits and insufficient solder.
X-ray inspection has become an indispensable means for components such as BGA that are difficult to directly observe. It can penetrate solder joints, check the soldering situation inside the components, ensure the correctness of soldering, and avoid problems such as missing or offset solder balls.
2、 Functional testing
ICT testing measures the electrical characteristics on a circuit board through pins or test fixtures. It mainly checks whether the values of components such as resistors, capacitors, and inductors are within the specified range, ensuring that the electrical connections of the circuit board are correct and error free.
FCT testing involves testing the circuit board at the entire system level, simulating actual working conditions, and verifying the overall performance of the circuit board. It connects analog or digital signal sources to ensure stable operation of the circuit board according to specifications.
3、 Environmental adaptability testing
Temperature cycling test, by cycling heating and cooling under extreme temperature conditions, verifies the reliability of PCB boards under temperature changes, which helps to discover problems such as cracks and delamination caused by material thermal stress.
Humidity testing is conducted on PCB boards in high humidity environments to evaluate their stability and performance under humid conditions. Humidity testing can help reveal potential issues such as corrosion and electrical leakage.
Mechanical impact testing simulates the impact experienced by equipment during transportation to verify the seismic resistance and reliability of PCB boards. This testing method helps ensure the stable operation of the circuit board in various harsh environments.
4、 Other specialized tests
1. ESD testing evaluates the anti-static discharge capability of the circuit board to ensure that it will not be damaged due to static electricity during operation and maintenance. This is of great significance for improving the overall reliability of electronic products.
Hardness testing of solder mask to evaluate its scratch resistance and wear resistance. This helps to extend the service life of PCB boards and reduce failures caused by surface wear.
Thermal stress testing and solderability testing are conducted to verify the heat resistance of PCB substrate and copper layer through high-temperature baking and cooling cycles. Solderability testing evaluates the soldering performance of printed circuit board surface conductors and through holes by simulating the soldering process.
