PCBA maintenance in SMT

In the process of production and use of SMT chip processing, it is inevitable that improper operation will occur in the whole PCBA manufacturing process and use process, including processing errors, improper use, aging of components and other factors, which may cause abnormal work, or even affect the use of the whole product. However, many products do not need to be replaced completely. At this time, it is necessary to repair and maintain the circuit board inside. The following is Kingford’s maintenance method.

Checking components

When the products in SMT SMT chip processing plant need to be repaired, it is necessary to first determine whether the components of each solder joint have any errors, omissions and reverses. It is also a situation to consider to confirm the authenticity of no materials. If the problems of errors, omissions, inversions, and authenticity are eliminated, we can get a faulty circuit board and first check whether the circuit board is intact and whether each component is obviously burned out and whether it is inserted correctly.

Welding status analysis

The defect of circuit board is basically 80% of the defect of solder joint. hether the welding of the joints is full and there are abnormalities, we must first refer to the ISO9001 quality system management standard. t is also necessary to refer to various SMT processing welding quality standards to check whether there are any visible defects such as false welding, false welding, short circuit, whether the copper skin is obviously lifted. If there is, we need to repair the defective points of this product, if not, you can proceed to the next step.


Component orientation detection

In this process, we have basically eliminated some of the defects that can be seen by the naked eye. Now we still have to carefully check the most used components on the circuit boards such as diodes, electrolytic capacitors, and other regulations on the direction, or Whether the required components of the negative electrode are inserted in the wrong direction.

Tool inspection of components

If all the visual judgments are correct, then we need to borrow some auxiliary tools at this time. The most commonly used in SMT chip processing plants is to use a multimeter to simply measure our components such as resistors, capacitors, transistors, etc. The main test is to check whether the resistance value of these components does not meet the normal value, whether it is larger or smaller, whether the capacitor is open, whether the inductor is open, etc.

Power-on test

After all the above processes are completed, the conventional problems of the components can be basically eliminated, and the circuit board will not be ablated and damaged due to short circuits or bridges. Then you can plug in the power and see if the corresponding function of the circuit board is normal.


After all processes are completed, according to our customer’s BOM, Gerber and schematic diagram, we can judge and repair the defects of the customer’s products. Choose Kingford!More professional !More assured!


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