PCBA Tech - What are the quality control of PCBA patch processing?

The following introduces the quality control of PCBA patch processing:

The production and processing process of PCBA involves a series of processes such as PCB board manufacturing, electronic component procurement and inspection supplied by PCBA, SMT chip processing, plug-in processing, program firing, testing, and aging. The supply chain and manufacturing chain are long. Any problem in any link will cause a large number of PCBA boards to fail the quality in batches, and cause undesirable consequences. In view of this situation, the quality control of PCBA patch processing is a very important quality assurance in electronic processing, so what are the main quality control of PCBA processing?

It is particularly important to hold a pre-production meeting after receiving an order for PCBA processing. It is mainly to analyze the process of PCBGerber files and submit a manufacturability report (DFM) according to different customer needs. Many small manufacturers do not pay attention to this, but tend to Here. 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 patches

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 with higher quality requirements and better processing requirements are required. According to the needs of PCB, some need to increase or decrease the steel mesh, or U-shaped holes, only need to make the steel mesh according to the 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 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 processing board test

For orders with PCBA test requirements, the main test content includes ICT (circuit test), FCT (functional test), burn test (aging test), temperature and humidity test, drop test, etc.