PCB Technical - How to choose PCBA, SMT processing factory

Here is an improper but more vivid analogy. Finding a suitable PCBA processing factory is like "falling in love and finding friends". The other party is too bad and you look down on it; the other party's strength is too strong, and others don't pay much attention to you. You may not be able to climb high for the time being. Therefore, you must be clear about your own conditions and requirements, and then find the ones that are more suitable for you, and the right ones are the best. I think the following aspects need to be paid attention to:

1. We must first know the types and requirements of PCBA processing orders. The type of PCBA order refers to whether the PCBA and SMT processing factories are intended to process only supplied materials, or OEM materials; whether the order quantity belongs to a sample small batch or a medium-to-large batch; whether the processing difficulty is medium-low difficulty or high-difficulty; is the price Priority or quality and service priority and so on. For example, if you have professional purchasing personnel, PCBA processing orders are not large, and quality and service are more important, you can choose SMT processing plants with complete equipment, more efficient management, better service awareness, and faster feedback speed instead of being in the factory. Excessive time and effort are spent on scale and processing price. If you want the other party to do OEM materials, then the review must be more detailed.

Component procurement is a very important part. PCB is the carrier for all other components to be used for patch and plug-in processing. It is very important. A good PCB supplier must be selected. Personal suggestion, if you have energy and time, it is best to provide PCB to SMT processing factory by yourself. Other electronic components are also very important. The channel of electronic materials generally determines their quality and price. Whether to use materials from Europe, America, Japan, South Korea and Taiwan, or domestic substitute materials, these must have clear requirements for PCBA processing plants., Cannot be changed easily.

2. The business philosophy, cooperation awareness and service attitude of the person in charge of the PCBA processing plant. If it is possible to see the SMT chip processing factory, it is best to meet the person in charge of the factory. You can prepare some questions in advance, communicate with the person in charge of the SMT chip processing plant, and understand the other party's business philosophy and sense of cooperation. Some persons in charge do not pay much attention to quality management, and are unwilling to try to cooperate from a small PCBA order. The factory employees have a weak sense of service and the feedback speed is very slow. If the person in charge thinks that low-level errors such as missing or reversed components during PCBA processing are relatively normal, then the level of quality management can be basically confirmed. In modern factories, advanced equipment is also very important, but in any case, people are the first, and it is difficult to make high-quality products without a strong sense of quality. If the person in charge of the PCBA processing plant feels that this level is inappropriate, I strongly recommend that it is not appropriate to cooperate, otherwise the two parties will be very painful.

3. Scale and equipment: The specifications generally depend on how many SMT lines the other party has, how many people, and the configuration of the plug-in line for wave soldering. The equipment is relatively simple. Modules such as Fuji, Panasonic, and ASM generally post large-volume orders, and small-volume orders are not appropriate. 3-6 SMT lines generally use Samsung, Juki, Yamaha SMT placement machines. The most important equipment is to look at the SPI solder paste detector, FAI first detector, X-ray, laser engraving machine and other equipment. Many medium-scale SMT processing plants, such as 6 SMT lines, are not equipped with SPI, FAI, laser engraving machines, wave soldering equipment, and if the management is not good, the quality is worrying. For PCBA processing, SMT patches have wire bodies, but plug-ins and post soldering are also required. Without wave soldering, generally only hand soldering or soldering can be done, and the quality cannot be well guaranteed. This is what we should consider when choosing a PCBA processing plant.

4. System certification and factory management: Most of the system certification depends on the ISO 9001 quality certification of PCBA processing plants, ISO13485 medical certification, and IATF16949 automotive certification. General factories must have at least ISO 9001, while other general small and medium-sized SMT processing factories do not. Although everyone knows that these certifications can be bought and sold, it depends more on whether the SMT factory can do it in daily management. The management of the factory depends on the 5S management of the workshop and warehouse, whether the area identification is clear, whether there is an air shower, whether the employees are wearing electrostatic bracelets, etc. For PCBA processing with BGA, whether there is X-ray for testing, whether it is sampling inspection or full inspection (generally, sampling inspection in the industry). After the furnace AOI is full inspection or random inspection, many factories in the industry also conduct random inspections, but if there is no guarantee that there will be no major quality problems such as missing or reversed components, why can't it be fully inspected (just to save costs)? I also learned that in the PCBA proofing stage and the manual soldering and cleaning stage of the PCBA mantissa, many factories only use visual inspection, and there is no concept of AOI inspection at all, and there is no guarantee that there will be no missing or reversed components. This approach is very worrying. AOI, especially offline AOI, 2D AOI is not a panacea, but compared to manual visual inspection, its error rate is obviously much lower.

5. Mounting technology and major customers who have cooperated: For SMT processing, it is basically machine work. For 90% of the current orders in the market, there is no problem. The problem lies in the management of the factories mentioned above. The difficult POP technology is not something that ordinary factories can do. Those that can do this are all large factories or SMT factories that focus on technology. On the other hand, if your PCBA order has a certain amount, and the PCBA processing factory has cooperated with a relatively well-known company for a long time, then the quality of the PCBA processing factory is still relatively reliable. You can also focus on this point when you visit the factory. .

The PCBA processing plant is not a tall PCB company, it is hard work and tiring work, and its focus is on the management and service of the factory.