There are many kinds of components in SMT chip processing, among which the flake component is the key of smt assembly and welding technology, which has an impact on the quality and reliability of the product. Flake components are miniature electronic components, and there are many types of models. They have different shapes and different physical properties.
The following matters need to be taken into account when mounting and welding:
1. Before welding, it is necessary to understand whether the components have special requirements, such as welding temperature conditions, assembly methods, etc. Some components cannot use the method of immersion tin, but only by electric soldering iron. Such as sheet potentiometers and aluminum electrolytic capacitors. So, it is necessary to choose the correct welding method according to the situation.
2. For components that require soldering, it is best to dip them only once. Multiple dipping of tin will cause bending of boards and cracking of components.
3. During the welding process, in order to prevent electrostatic damage, the soldering iron and solder furnace should have good grounding device.
4. The selection of printed boards should be small thermal deformation, copper foil overlay. Due to the narrow copper foil surface assembly and small pad, if the anti-stripping ability is insufficient, the pad will easy to peel off. So, generally choose epoxy glass fiber substrate.
5. For rectangular flake capacitors, it is easy to weld with larger appearance, such as type 1206, but is prone to crack and other thermal damage due to uneven welding temperature. While those with smaller appearance, such as type 0805, are more difficult to weld. However, cracks and thermal damage are not easy to appear, and the reliability is high.
6. If the pcb board needs to be repaired, the number of disassembly and assembly of components should be reduced as much as possible, because multiple assembly and disassembly will lead to complete scrapping of the PCB. In addition, the mixed printed circuit board may be removed first if it interferes with the insertion and detachment of the chip components.
The welding of flake components is very complicated in smt chip processing. The operator should learn the welding skills and understand the matters needing attention carefully to avoid errors and affect the welding quality.