Some basic knowledge of pcba testing

2、Some common PCBA tests and precautions

Visual inspection

Visual inspection relies on professional technicians to use their experience to observe with the naked eye or a magnifying glass to initially check for obvious PCBA assembly errors, such as component misinstallation, reverse installation, abnormal solder joints, etc. Although this process seems simple, it is an important prerequisite for subsequent precision testing.

Note: During the visual inspection process, technicians must strictly abide by lighting conditions, magnification and other requirements to ensure that all details of solder joints, components and identification information are captured. At the same time, clear defect determination standards need to be formulated to improve the consistency of visual inspections.

ICT testing (In-Circuit Testing)

ICT testing is an online testing method based on circuit schematics. It can accurately measure the electrical parameters of each component on the PCBA and the connectivity between circuit nodes, and effectively identify faults such as poor welding and component damage. It is an important way to ensure the function of the circuit board. Complete basic testing methods.

Note: Before conducting ICT testing, be sure to ensure that the test program matches the actual PCBA version to avoid misjudgment caused by design changes. In addition, regular maintenance of test fixtures and calibration of test equipment can prevent equipment errors from affecting the accuracy of test results.

FCT Functional Circuit Test

FCT testing focuses on overall functional verification. By simulating the real working environment and user operations, it comprehensively assesses whether the various functions of the PCBA are operating normally. This end-to-end testing method is crucial to ensuring the user experience of the final product.

Note: The FCT test scenario should simulate the real application environment as much as possible to reflect the actual performance of PCBA. When writing test scripts, fully consider boundary conditions and exceptions to ensure that all functional modules can be fully verified.

AOI automatic optical inspection (Automated Optical Inspection)

AOI uses high-resolution cameras and advanced image processing technology to conduct high-speed, automated optical inspection of PCBA solder joints and component mounting. It is especially good at capturing subtle defects that are difficult to identify with the naked eye, greatly improving production efficiency and quality control levels.

Note: AOI equipment needs to regularly update algorithms and databases to adapt to changing component specifications and welding processes. At the same time, clean the lens in time to maintain the stability of the optical system to avoid false positive or false negative test results.

X-Ray detection

With its unique perspective ability, X-Ray inspection can penetrate packaging materials, clearly reveal the internal structure of hidden solder joints such as BGA and CSP, and effectively detect hidden dangers such as solder joint voids, short circuits, and offsets. It is an indispensable tool for modern high-density package PCBA. Indispensable detection tools.

Note: When performing X-Ray inspection, pay attention to setting appropriate exposure parameters to obtain clear images and accurately determine the internal structure of solder joints such as BGA and CSP. Additionally, operators should have extensive interpretation experience to quickly identify potential problems. At the same time, comply with radiation safety regulations and use protective equipment correctly to ensure personnel safety.

Flying probe test

Flying probe testing uses flexible moving probes to directly contact the points to be tested. It is suitable for all types of complex PCBA products with frequent design changes. It has high flexibility and pertinence, especially in the new product development stage and small batches and multiple varieties. Show strong advantages.

Note: Before flying probe testing, make sure the probes are in good contact and not damaged to prevent false alarms or false negatives. At the same time, adjust test strategies for different PCBA layouts, especially when facing high-density interconnect designs, to ensure that probes will not cause damage to sensitive components.

Aging test

The aging test places PCBA under specific environmental stress (such as high and low temperature cycles, long-term continuous operation, etc.) and observes its performance changes to evaluate the stability and life of the product during long-term use, and to discover and solve potential problems in advance. Failure problem.

Note: The aging test environmental conditions (temperature, humidity, load, etc.) need to simulate real usage scenarios, and PCBA performance indicators must be continuously monitored within a long enough time period. Record detailed test data for analyzing product reliability trends.

High voltage test

High-voltage testing is mainly used to test power modules, insulation materials, and protective designs. By applying voltage tests that are much higher than the normal operating voltage, it is confirmed that PCBA has good insulation tolerance and impact resistance under abnormal conditions.

Note: During high-voltage testing, strictly abide by safe operating procedures and take protective measures such as grounding and isolation to prevent personal injury and equipment damage caused by electric shock accidents. Setting a reasonable voltage boost speed and test time can not only effectively detect insulation problems, but also avoid abnormal breakdown caused by too fast and too high voltage.High voltage test

As the global electronics industry enters a new era of intelligence, miniaturization, and high speed, PCBA testing is also undergoing new changes. First of all, intelligence will be the core driving force for PCBA testing. AI and machine learning technology will be deeply integrated into the testing process, enabling test equipment to have the ability to self-learn and optimize. It can not only predict and prevent potential quality problems in advance, but also dynamically adjust testing strategies to adapt to increasingly complex circuit designs. This intelligent trend will greatly improve the accuracy and efficiency of testing, reduce production costs, and improve the overall quality level. Secondly, fully automated and unmanned test production lines will gradually become mainstream. From material preparation, patching, and welding to inspection, trimming, and packaging, the entire PCBA production link will achieve seamless automated operations. In particular, the collaborative work of AOI, X-ray inspection equipment and robot arms will greatly improve the inspection speed and accuracy and realize true intelligent manufacturing. Furthermore, virtual testing and simulation technology will be widely used. Based on advanced computer-aided design (CAD) tools and high-performance computing platforms, engineers can conduct detailed virtual testing and performance simulation of products before they are actually produced, discover problems early and optimize designs, thereby shortening the product development cycle and reducing costs. , enhance market competitiveness. In addition, integrated, modular and portable test solutions will also be sought after. Future PCBA test equipment will be smaller and lighter, allowing for flexible deployment and rapid switching on the production line to cope with diversified production needs and rapidly changing market environments.

XingHongTai Company has always adhered to the principle of continuous innovation and has been thinking about the innovation potential that has not been fully explored in the rapidly developing industry of electronic manufacturing. For example, cutting-edge technologies such as IOT (Internet of Things), edge computing, and quantum computing can be combined and applied like PCBA testing. XingHongTai also has the world’s leading electronic manufacturing technology and a strong engineering team to help you solve any degree of difficulties encountered in different products. XingHongTai is very confident to become your most trusted partner. If you happen to have needs in this area, you can click here —contact us.