Electronic Design - How is the PCB board welding method designed?

At present, in chip processing factories, it is a wide range of PCB boards to use visual soldering machines to solder. In order to better use the visual soldering machine, it is necessary to know the precautions of the PCB board and the soldering machine, so as to achieve a better soldering effect. So how does the visual soldering machine work when soldering the PCB board?

First of all, the surface of the weldment of the PCB board or PCBA board should be cleaned by the SMT processing operator of the PCB factory. In order to achieve a good combination of the solder and the weldment, the surface of the weldment must be kept clean, even if it is a weldment with good solderability. If there is an oxide layer, dust, and oil on the surface of the weldment, it must be cleaned before soldering, otherwise, it will affect the formation of the alloy layer around the weldment, and the quality of the solder cannot be guaranteed.

Secondly, the weldment must be solderable. The quality of soldering mainly depends on the ability of the solder to wet the surface of the weldment, that is, the wettability of the two metal materials is the weldability. If the weldability of the weldment is poor, it will not It is possible to weld qualified solder joints. Solderability refers to the performance of the weldment and solder to form a good bond under the action of appropriate temperature and flux.

Next, the setting of soldering time for PCBA circuit board and PCB circuit board patch processing should be appropriate. Soldering time refers to the time required for physical and chemical changes in the soldering process. It includes the time for the solder to reach the soldering temperature. The melting time of the solder, the time for the flux to work, and the formation of the metal alloy are several parts.

With the continuous improvement of technology, some of the above-mentioned PCB board electronic components have been wave soldered or patched, with high efficiency and more reliable stability. The remaining components cannot pass the furnace and cannot be pasted. After the soldering process of the automatic soldering machine is solved, there are many actual cases encountered in PCB circuit board soldering. Usually, the engineering department of the factory will make process improvements and require more stable and reliable soldering methods. Their starting point is PCB Circuit boards that require more stable quality and high efficiency.

In SMT processing, the reasonable planning and design of PCB are the key steps to ensure product quality in SMT processing. The main basic working processes are as follows:

1, PCB layout. Mainly to plan the physical size of the PCB board, the packaging form of the components, the installation method of the components and the layer structure (that is, the choice of single-layer, double-layer and multi-layer boards).

2. Working parameter setting. Mainly refers to the working environment parameter setting and the working layer parameter setting. Setting the PCB environment parameters correctly and reasonably greatly facilitates the design of the circuit board and improves the work efficiency.

3. Component layout and adjustment. This is a relatively important task in PCB design, it directly affects the wiring and the distribution of the internal electrical layer on the back, so it needs to be handled carefully. After the current work is ready, you can import the netlist In the PCB, you can also directly import the netlist by updating the PCB in the schematic diagram. You can use the automatic layout and the function of the ProtelDXP software. However, the automatic layout effect is often not very ideal. Generally, a manual layout should be used, especially for complex circuits and Special requirements for components.