PCBA Tech - What aspects of PCBA patch processing need to pay attention to

What aspects of PCBA patch processing need to pay attention to
The production process of PCBA involves a series of processes such as PCB board manufacturing, electronic component procurement and inspection supplied by PCBA, SMT chip production and processing, plug-in production and processing, program firing, testing, and aging. The supply chain and manufacturing chain are long. Defects in the other stage will cause the PCBA board to fail in mass quality and cause serious consequences. For such a situation, the quality control of PCBA patch processing is a very important quality assurance in electronic processing, so what are the key to the quality control of PCBA processing?
It is extremely important to hold a pre-production meeting after receiving the PCBA patch production and processing order. It is mainly to conduct process analysis on PCBGerber files and submit manufacturability reports (DFM) according to different customer needs. Many small manufacturers do not pay attention to this, but Tend to lean towards this. Not only is it prone to poor quality problems caused by poor PCB design, but also a lot of rework and repair work.
2. Purchase and inspection of electronic components supplied by PCBA
It is necessary to strictly control the procurement channels of electronic components, and must obtain goods from large traders and original manufacturers, so as to avoid the use of second-hand materials and counterfeit materials. In addition, it is necessary to set up a special PCBA incoming material inspection post to strictly inspect the following items to ensure that the components are fault-free.
PCB: Check the temperature test of the reflow oven, whether the fly-line vias are blocked or leaking, whether the board surface is bent, etc.
IC: Check whether the screen printing is exactly the same as the BOM, and store it at constant temperature and humidity.
Other commonly used materials: check screen printing, appearance, power measurement, etc.
3. SMT assembly
Solder paste printing and reflow oven temperature control system are the key points of assembly, and laser stencils that have higher quality requirements and can better meet the requirements of production and processing are required. According to the requirements of PCB, some steel mesh holes or U-shaped holes need to be added or reduced, and steel mesh can be made according to process requirements. Among them, the temperature control of the reflow oven is very important for the wetting of the solder paste and the firmness of the steel mesh, and can be adjusted according to the normal SOP operation guide.
In addition, strict implementation of the AOI test can greatly reduce the defects caused by human factors.
4. Plug-in production and processing
In the plug-in process, the mold design for wave soldering is the key. How to use the mold to maximize the yield rate is a process that PE engineers must continue to practice and summarize.
5. PCBA patch production and processing board test
For orders with PCBA test requirements, the key test content includes ICT (circuit test), FCT (functional test), burn test (aging test), temperature and humidity test, drop test, etc.