PCBA repair in SMT patch processing

2021-01-05 12:34:29 hongling

PCBA repair in SMT patch processing

        In the production and use process of SMT chip processing, because of problems in the entire PCBA manufacturing process and use process, including processing errors, improper use and aging of components, there will be abnormal work or even poor use of the actual product. . Because many products just don't need all replacements. This requires certain repairs and maintenance of the circuit boards inside. Then it involves the maintenance of the circuit board! Today, the editor of JKR Jingkerui is here to briefly share some experience and skills of circuit board repair technology. If you want to learn circuit board repair technology systematically, you can click on the official website of JKR Jingkerui. We will regularly share some SMT processing plants with you. Practical tips, including but not limited to maintenance:

        Generally, the maintenance technology in our patch processing plant will perform the following operations.

        1. Check the components

        When the products in the SMT chip processing plant need to be repaired, the first thing to do is to determine whether there are errors, omissions, and reverses in the components of each solder joint. Confirming the authenticity of no materials is also a situation that needs to be considered. If the problems of error, leakage, reverse, and authenticity are eliminated, you can get a faulty circuit board. First check whether the circuit board is intact and whether the various components are obviously burnt out and plugged in.

        2. Analysis of welding status

        Basically 80% of the defects of the circuit board are the defects of the solder joints. Whether the solder joints are full and whether there are abnormalities, first of all, please refer to the management standards of the ISO9001 quality system, as well as various SMT processing and welding quality standards, and check whether there is any Visual defects such as false welding, false welding, short circuit, and whether the copper skin is obviously lifted. If so, you need to repair the defective points of this product, if not, you can proceed to the next step!

        3. Detection of component orientation

        In the process of this link, we have basically eliminated some defects that can be seen with the naked eye. Now we still need to carefully check the diodes, electrolytic capacitors, the most used components on the circuit board, and other components that have directions or are positive. Whether the components required by the negative pole are inserted in the wrong direction.

        4. Tool inspection of components

        If all visual judgments are no problem, we need to borrow some auxiliary tools at this time. The most commonly used in SMT patch processing plants is to use a multimeter to simply measure our resistance, capacitance, transistor and other components, with a multimeter. The most important thing to check is to check whether the resistance values of these components are not up to the normal value, become larger or smaller, whether the capacitance is open, whether the inductance is open, etc.

        5. Power-on test

        After all the above processes are completed, the conventional problems of the components can basically be eliminated, and there will be no ablation damage to the circuit board due to short circuits or bridging. You can turn on the power and check whether the corresponding function of the circuit board is normal

        After basically all the processes are over, the customer’s BOM and Gerber can be eradicated, and the schematic diagrams can be used to judge and repair the defects of the customer’s products. In the patch processing plant, the technicians in our maintenance department are carefully selected from the workshop Professional players.