1.What is SMD?

It is the abbreviation of Surface Mounted Devices. It covers a very wide range, from small resistors to complete integrated circuits, almost all various electronic products contain SMD devices. Generally, the size of relatively simple SMD components is displayed with 4 as the code. It can be seen from the above that the SMD component is very small, so its soldering is also difficult.

2.What tools are needed for SMD soldering?

A. How to choose the right soldering iron tip:

When soldering SMD components, the selection of the soldering station is the most important part. While choosing a good soldering iron tip is more important than a good soldering station, because even with our AiXun smart soldering station, soldering work cannot be done without a good soldering iron tip. When choosing a soldering iron tip, it is most important to choose the one that matches the size of the SMD components being soldered. These components have different widths and pads of different sizes, so the selection of an appropriately sized soldering iron tip makes soldering job easier. AiXun recommends that we choose a pointed tip between 1 and 2 mm. Due to their shape, they are ideal for heat transfer.

B. Choice of Solder:

The choice of solder depends on the components you are soldering, but if you are soldering electronic products, lead-free solder is the best choice. Considering environmental protection, the pollution caused by lead-free solder is relatively small, so it is the best recommendation. Nowadays, the solders used in printed circuit boards are almost all lead-free solders. Lead-containing solder and lead-free solder cannot be mixed. If lead-containing solder is to be used, the pad must be thoroughly cleaned to ensure smooth soldering.

 

• Choice of flux:

Flux is essential for simple soldering jobs. Because when the flux is placed on the printed pad, the solder will automatically flow to the correct location. The step of soldering the pins to each other is omitted.

• In addition to the above tools, some other tools are required. For example, a magnifying glass helps us to align the correct position of the pad where the component is located during soldering, and at the same time, we can also use the magnifying glass to distinguish whether the soldering line is correct, and check whether the welded components are in good condition to improve the soldering accuracy and efficiency. The clip is also very important when soldering, because it is equivalent to a third hand when soldering, which can help us clamp components that we can't reach with our hands and that we can't touch due to temperature.

 

3. How is SMD soldering done?

SMD soldering requires many steps. It is also very important whether these steps can be performed quickly and whether the soldering materials and pads are clean. Therefore, it is necessary to ensure the cleaning of the soldering equipment and the pad before soldering.

A. The first step is to tin the pads where the components need to be soldered.

B. Then use tweezers to clamp one leg of the component to be soldered with the left hand, and solder the remaining pins with tin wire.

C. After gently pressing the soldering iron tip on the welded joint, quickly remove the soldering iron tip and wait for cooling.

D. After cooling, check the soldering status of the welded part, whether it is a spherical joint, and how bright the soldering is. If the soldering joint is dark, it is necessary to check whether it is false soldering or fake soldering. If it is, it needs to be re-soldered according to the above steps.

E. After the soldering is completed, turn off the power and place the soldering iron on the soldering iron holder. After waiting for it to cool down, unplug it. 

 

 

4.SMD soldering skills:

 

A. For different component sizes, the easiest way is to solder from small to large.

B. Do not heat a large area during soldering, because the periphery of the soldering component will be loosened due to the heating of the soldering iron tip, causing damage to other components. So make sure that the temperature of the pad is cold when soldering.

C. Keep the soldering iron tip clean. When soldering SMD, the soldering iron tip must be kept very clean. Because oxidized solder is a poor conductor, it can also contaminate the solder to be made.

D. The sponge must be wet, but not too wet. Because the temperature of the soldering iron tip will drop sharply if it is too wet.

E. The amount of solder should be moderate. Excessive solder not only consumes the expensive tin unnecessarily, but also increases the soldering time and reduces the working speed.