PCBA Tech - Solder joint quality and pcba manufacturer's production

1. The quality of solder joints in SMT chip processing

With the development of technology, some electronic devices such as smart phones and tablet computers are becoming lighter, smaller, and portable. The electronic components used in SMT processing are also continuously shrinking. The previous 0402 resistors and capacitors have also been largely used 0201 size is given instead. How to ensure the quality of solder joints has become a key issue for high-precision placement. The solder joint is used as a bridge for soldering, and its quality and stability determine the quality of electronic equipment. In other words, in the process of processing, the quality of SMT patch processing is ultimately manifested as the quality of solder joints.

1. Judgment of Welding

1. Select professional online tester equipment for testing.

2. Visual inspection or AOI inspection. When it is found that there is too little solder material in the solder joint, solder penetration is not good, or there is a crack in the middle of the solder joint, or the surface of the solder is convex, or the solder is not compatible with SMD, etc., you need to pay attention to it, even in a slight condition. Causes hidden dangers, it should be immediately judged whether there is a lot of false welding problem. The method of judgment is: to see if there are many solder joints at the same position on the PCB, such as the problem on some PCBs, it may be due to scratching of the solder paste, pin deformation, etc., such as on many PCBs. There is a problem with the same position. At this time, it is likely to be caused by a bad component or a problem with the pad.

Second, the cause of the virtual welding and its solution

1. The pad design is defective. The existence of through-holes in the pads is a major disadvantage of PCB design. If it is not necessary, it is not necessary to use them. The through-holes will cause the loss of solder and lead to insufficient soldering materials. The spacing and area of the pads also need to be standardized, otherwise the design should be corrected as soon as possible.

2. The PCB board is oxidized, that is, the pad is black and does not shine. If there is oxidation, you can use an eraser to remove the oxide layer to make it bright again. If the PCB board is damp, it can be dried in a drying box if suspected. The PCB board has oil stains, sweat stains and other pollution, so use absolute ethanol to clean it up.

3. For PCBs that have been printed with solder paste, the solder paste is scratched and rubbed, which reduces the amount of solder paste on the relevant pads and makes the soldering material insufficient. Should be added immediately. You can use a dispenser or use a bamboo stick to pick a little supplement.

The above content is related to the quality of solder joints in SMT chip processing

Second, how does the PCBA manufacturer produce

The main task of the PCBA manufacturer is to print the wiring board. Various integrated circuits and electronic parts are installed on the printed wiring board by the PCBA manufacturer and welded to form a computer color TV. The PCBA is the main board of the communication device, which is a circuit board in simple and easy to understand.

In fact, the production range of PCBA manufacturers is very vague. There are many kinds of motherboards and chips. But we only need to know that the essence of the main production scope of PCBA manufacturers is to produce circuit boards. The popular SMT surface mounting technology and our initial through-hole mounting technology are several key technologies produced by our PCBA manufacturer. The core method is to "paste" components to the wiring board, through-hole mounting technology It is to insert the parts we need into the through holes of the wiring board for soldering.

The birth of the PCBA manufacturer is called the revolution of the electronic alliance. This is also the revolution of our PCBA generation, and the relationship between electronic installation and PCBA generation is very close. Essentially, they are all processing operations on the basic electronic board, and the processing technology used is basically the same.

Among PCBA manufacturers, two steps are the most difficult and complicated. The component mounting process of our PCBA manufacturer is to pick up the surface-mounted components from the feeder of the automatic mounting machine and mount them on the printed PCBA substrate. Although it is not so difficult for us, when you do the real thing, you will find that you are unfamiliar and wrong.

This is the previous step. If you take the wrong step, you will take the wrong step. It is difficult to make PCBA production. As for our parts installation, through-hole installation parts and some surface-mount parts that cannot be installed by machines, such as some The electrolytic capacitor connector button switch and metal terminal electrode parts, etc., are either manually installed or installed through an automatic installation device. Therefore, the existence of PCBA manufacturers has reduced a lot of unnecessary troubles, saved a lot of time for our other enterprises, and provided high efficiency.