1.Common soldering methods can be divided into electric soldering iron soldering, heating platform soldering and reflow soldering soldering, etc.:A, electric soldering iron soldering is the most common, such as sample preparation and repair, because most existing manufacturers buy back electricity in order to save costs. Soldering irons are mostly unqualified and slightly quality products, and most of them are poorly grounded and have leakage. During the welding process, this is equivalent to forming a loop between the leaking soldering iron tip-the soldered LED-the human body-the earth, which is equal to the number Ten times-hundreds of times the voltage that the lamp bead bears is applied to the LED lamp bead, which instantly burns it out.B. Dead lights caused by welding of heating platform. Due to the continuous sample list of lamps, most companies meet the needs of small batches and sample lists. Due to the advantages of low equipment cost, simple structure and operation, heating platform has become the best production tool However, due to the use environment (such as the problem of instability in the temperature where there is a fan), the welding operator’s proficiency and the control of the welding speed have become a major problem of dead lights, and there is also heating Equipment grounding of the platform.C, reflow soldering. Generally, this soldering method is the most reliable production method, suitable for mass production and processing. If the operation is not performed properly, it will cause more serious consequences of dead lights, such as unreasonable temperature adjustment, poor machine grounding, etc.
2. Dead lights caused by improper storage: This kind of problem is the most common, because the problem of moisture prevention is not paid attention to after opening the package, because the sealing glue of the lamp beads is mostly silica gel, which has certain water absorption characteristics, and the lamp beads are attached after being damp. After the board, after the high-temperature soldering process, the silica gel will expand and contract with heat, the gold wire, chip, and the bracket will deform, causing the gold wire to shift and break, and the lamp will not turn on. Therefore, it is recommended that the LED should be stored in a dry and ventilated place. In the environment, the storage temperature is -40℃-+100℃, and the relative humidity is below 85%; the LED should be used up within 3 months under its original packaging condition to avoid rusting of the bracket; when the LED packaging bag is opened After that, it should be used up as soon as possible. At this time, the storage temperature is 5℃-30℃, and the relative humidity is below 60%.
3. Chemical cleaning: do not use unknown chemical liquids to clean the LED, because that may damage the surface of the LED colloid, or even cause cracks in the colloid. If necessary, please clean it with an alcohol swab under normal temperature and ventilation. The time is best to control within one time. Minute wind is complete.
4. Dead light caused by deformation: Because part of the light board is deformed, the operator will go to reshape it. Due to the deformation of the board, the lamp beads above will also deform at the same time, pulling the gold wire, causing the light to fail. It is recommended This type of board is best to be reshaped before production. Longer production, assembly and movement may also cause deformation to break the gold wire. There is also stacking. In order to facilitate the production process, the lamp boards are stacked at will. Due to gravity, the lower lamp beads will be deformed by force and damage the gold wire.
5. The heat dissipation structure, power supply and light board do not match: due to unreasonable power supply design or selection, the power supply exceeds the maximum limit that the LED can withstand (overcurrent, instantaneous impact); unreasonable heat dissipation structure of the lamp will cause dead lights and excessive Early light decay.
6, Factory grounding: It is necessary to check whether the main grounding wire of the factory is good.
7, static electricity: static electricity can cause LED function failure, it is recommended to prevent ESD from damaging the LED. A. Operators must wear anti-static wristbands and anti-static gloves during LED testing and assembly. B, welding equipment and testing equipment, work tables, storage racks, etc. must be well grounded. C. Use an ion fan to eliminate static electricity generated by friction during storage and assembly of the LED. D, the material box with the LED is an anti-static material box, and the packaging bag is an electrostatic bag. E. Don’t be lucky, just touch the LED
