PCB Technical - Method selection of PCBA processing in PCBA testing

In the design of PCB circuit boards, there are numerical relationships such as voltage and current between different test points. However, the process flow of PCBA processing is very complicated, including multiple important processes such as PCB board manufacturing process, component procurement and inspection, SMT patch assembly, DIP plug-in, PCBA testing, etc. During the production process, it may be due to equipment or improper operation. Various problems occur, so it is necessary to use professional test equipment or manual operation of a multimeter to test the test points to verify whether the actual PCBA board meets the design requirements and ensure that each product does not have quality problems.

PCBA circuit boards generally undergo strict electrical and performance tests before being delivered to customers. In PCBA testing, the most common ones are FCT functional testing and ICT electrical component testing. When PCBA first began to emerge, ICT became the mainstream,

including many large electronic product design companies. For example, the mobile phone industry still uses the ICT model to conduct rigorous testing on all original components, so that it can quickly detect whether the components on the circuit board comply with their design. Values and parameters to avoid the tragedy of a single capacitor overturning the entire circuit board.

However, with the rapid development of the semiconductor industry, the density of electronic components has become higher and higher, and the production process and stability of its production have become more mature, which has made the application range of ICT testing narrower and narrower. Many small and medium-sized PCBA electronics manufacturing and processing plants basically no longer use ICT testing as the mainstream mode, and begin to gradually pay attention to FCT functional testing. The factory generally requires the customer to provide an FCT test plan, including the test procedure, the issuance of the test frame and the related test steps, so that all PCBAs will undergo strict FCT testing before shipment and then be delivered to the customer.

Another reason FCT replaces ICT is cost. FCT is generally cheaper. It is customized according to the customer's design plan. The cost of the test rack is usually between 1,000 and 5,000. However, ICT equipment needs to be provided by professional manufacturers, and its cost ranges from tens of thousands to hundreds of thousands. In addition, because ICT needs to cover a lot of components, it makes the production of thimble platform extremely complicated, difficult, and costly. Therefore, ICT testing is currently more commonly found in general-purpose equipment and product production lines with huge shipments.

More and more ICT equipment manufacturers begin to integrate FCT functions in their equipment, and this trend has become increasingly obvious. However, it is difficult to standardize the functions of FCT testing, which makes it more difficult to develop general-purpose FCT test equipment. At present, the mainstream in the market is to customize according to different models and products of customers. Usually, the corresponding test rack and test platform are customized according to the customer's FCT design plan. The general cycle is completed within 3 to 7 days, and the cost is within 3,000 to 10,000 yuan. It is more suitable for flexible and changeable PCBA processing small and medium-sized enterprise production mode scenarios.