In order to ensure the quality and performance of the circuit board meet the standards, a series of strict inspection processes must be carried out before leaving the factory. These inspections can not only detect potential defects, but also ensure the stability and reliability of the circuit board during use.
1. Appearance inspection: Check the surface of the circuit board for scratches, contamination, missing prints, misalignment and other defects through manual or AOI (automatic optical inspection) system. By using image comparison technology, small defects such as pinholes, scratches, etc. can be efficiently detected.
2. Dimensional measurement
The size of the circuit board must be strictly produced according to the design requirements, and size measurement is usually carried out using professional tools such as laser measuring instruments, calipers, and coordinate measuring machines. By comparing the actual size of the circuit board with the design size, the accuracy of the circuit board is ensured to meet the technical requirements.
3. Electrical performance testing
Electrical performance testing is a crucial step before the circuit board leaves the factory, which mainly includes testing of circuit connectivity, impedance, and voltage. Common electrical testing methods include short-circuit testing, impedance testing, and withstand voltage testing.
4. Functional testing
Functional testing is the process of verifying the functionality of a circuit board by simulating its usage in actual operation. Typically, functional testing involves connecting the circuit board to other components of an electronic device and testing its performance in actual operating conditions. Functional testing includes but is not limited to: signal transmission capability, component functionality, data processing capability, etc.
5. X-ray examination
For multi-layer circuit boards, X-ray inspection is an essential inspection method. As the internal circuits of multi-layer circuit boards cannot be directly observed, X-ray inspection can capture voids, virtual soldering, short circuits, and other potential problems in the hidden layers by penetrating the interior of the circuit board.
6. Hardness and high temperature resistance test of sheet metal
The hardness and temperature resistance of circuit boards are crucial for their stability. Through board hardness testing, it is ensured that the circuit board is not easily deformed and can withstand the pressure in the actual working environment. In addition, high temperature resistance testing can verify whether the circuit board can maintain stable physical and electrical properties in high temperature environments, preventing deformation or material aging at high temperatures.
7. Chemical corrosion testing
Chemical corrosion testing is used to detect the quality of surface coatings on circuit boards, especially in harsh environmental applications such as marine and industrial environments. This test typically simulates corrosive environments to test the corrosion resistance of circuit boards.
8. Environmental testing
Environmental testing mainly simulates the working conditions of circuit boards under different temperature, humidity, and vibration conditions to check whether they can work stably in various unfavorable environments.
