1. Printing solder paste (LTCL-SP600). First, stir the solder paste back to the temperature (LF-180A can be used directly), and then put a small amount on the printing machine (LTCL-SP600) steel net. When the scraper advances, it is better to apply the solder paste to the 3/2 of the scraper. . After the first test, pay attention to observe whether the solder paste on the LED pad on the FPC is full, whether there is less tin or more tin, and pay attention to whether there is a short circuit. This level is very crucial, and the lack of strictness will result in poor quality in the back.
2, Patch (SM421S). Place the printed FPC on the fixture (Li Feng can fix the fixture) and automatically send the board to the placement position. The program of the placement machine is pre-programmed, as long as there is no problem with the first board placement, the production will be stable afterwards. What needs to be noted here is that the polarity of the LED and the resistance of the chip resistor should not be mixed. In addition, it should be noted that the position of the mounting should not be offset.
3. Intermediate inspection links. Need to pay attention to check the polarity of the LED on the LED light (with or without reverse), the placement is not offset, there is no short circuit, the resistance value is correct.
4. Reflow soldering (M6/S6). It should be noted here that the temperature of the reflow must be controlled well. Too low solder paste can not be melted, cold welding will occur; too high FPC is easy to foam. There is also the preheating temperature should be appropriate, too low flux volatilization is not complete, there is residue after reflow, affecting the appearance; too high will cause the flux to volatilize prematurely, causing the phenomenon of soldering during reflow, and may produce tin Beads.
5, Finished product inspection. Here you need to check the appearance of the product to see if there are poor soldering, solder balls, short circuits, etc. Then there is the electrical inspection to test whether the electrical properties of the product are intact and the parameters are correct.
6, Packaging. The package of LED light strips is generally 5 meters per roll and is packed in anti-static moisture-proof packaging bags. When attaching the package, please pay attention to the accessories, so as not to be able to use the customer due to lack of accessories.