Solving the problem of missing printing and less tin in SMT processing
1. Find all the pads that are not connected to the outer layers, change the size of these pads from the original circle with a diameter of 0.27 to a circle with a diameter of 0.31, reduce the area of the deep pit around the pad, and make the original opening area on the deep pit. It becomes on the copper foil of the pad, so that the gap between the opening area originally on the deep pit and the bottom of the stencil is reduced. After the small batch verification is OK, the original stencil is used in the mass production, and the pads that were originally difficult to tin have good tin (increase the pad area, and no poor tin connection is found in batch verification).
2. Reduce the thickness of the PCB solder mask and reduce the influence of the higher solder mask layer on the line near the pad. It is recommended that the PCB solder mask thickness be less than 25um.
3. The new PH stencil is adopted to eliminate the printing gap to the greatest extent. The introduction of PH stencil.
Shenzhen Baiqiancheng Electronics Co., Ltd. has its own factory in Shenzhen. At present, there are 16 SMT production lines and 4 THT lines. It has 19 years of production experience and rich experience, which can minimize the occurrence of problems such as less tin. and have rich experience to deal with these problems to ensure the high quality of products.
