During the production and use of SMT patchprocessing, problems will occur due to factors such as processing errors,improper use, and component aging due to problems in the entire PCBAmanufacturing process and use. . Because many products just don't need allreplacements. This requires certain repairs and maintenance of the circuitboard inside. Then it involves the repair of the circuit board!
In general, the maintenance technology in our patchprocessing factory will perform the following operations.
1. Check components
When the product needs to be repaired in the SMTpatch processing plant, it is first necessary to determine whether thecomponents of each solder joint have errors, leaks, and inversions. Confirmingthe authenticity of no materials is also a situation that needs to beconsidered. Not all are stronger than Huabeibei. If the problems of error,leakage, inversion and authenticity are ruled out, you can get a faulty circuitboard and first check whether the circuit board is intact and whether thevarious components are obviously burned out and inserted correctly.
2. Analysis of welding status
Basically, 80% of the defects of the circuit boardare the defects of the solder joints. Whether the solder joints are full andwhether there are abnormalities, first of all, please refer to the managementstandards of the ISO9001 quality system, and various SMT processing weldingquality standards, check whether there are Defective welding, false welding,short circuit, whether the copper skin is obviously raised and other defectsthat are visible to the naked eye. If there is, you need to repair thedefective points of this product, if not, you can proceed to the next step!
3. Detection of component direction
In the process of this link, we have basically ruledout some defects that can be seen by the naked eye. Now we must carefully checkthe diodes, electrolytic capacitors, etc. The most used components on thecircuit board, there are other provisions on the direction, or positive Are therequired components of the negative pole inserted in the wrong direction?
4. Tool inspection of components
5. If all the naked eye judges that there is no problem, we need to borrowsome auxiliary tools at this time. The most commonly used in SMT patchprocessing factory is to use a multimeter to simply measure our resistance,capacitance, triode and other components, use a multimeter The most importantthing to check is to check whether the resistance value of these componentsdoes not meet the normal value, become larger or smaller, whether the capacitoris open, whether the inductance is open, etc.
5. Power-on test
After the above process is completed, theconventional problems of the components can be basically eliminated. If thepower is turned on, there will be no ablation damage of the circuit board dueto short circuit or bridging. You can turn on the power and check whether thecorresponding function of the circuit board is normal
Basically, after all the processes are completed,the BOM and Gerber of the customer are eradicated, and the schematic diagramscan be used to judge and repair the defects of the customer's products. In thepatch processing plant, our technicians in the maintenance department arecarefully selected from the workshop Professional player.