When soldering the chip contacts, you can prepare some rosin, although it is not necessary, but its presence can help the welding process smoother.
First, clean the chip contacts to remove the oxides and impurities on them. The solder wire is then placed on the contact, and the solder is heated and melted using a soldering iron. When melting the solder, some rosin can be added appropriately, which helps to increase the fluidity of the solder and make it easier to penetrate into the gap between the contacts.
After the solder has fully melted and penetrated into the contact gap, remove the soldering iron and allow the solder to cool naturally. After cooling, check the welding effect to ensure that the contacts are fully connected and that there is no false welding or missing welding. In short, when soldering the chip contacts, adding some rosin can help make the welding process smoother, but it is not necessary. It should be noted that the temperature and time should be controlled during the welding process to avoid damage to the chip and other components.
Rosin is surrounded by solder wire inside, when the solder melts, rosin with the solder down, mainly to make the role of condensation.
When the chip pin is welded, melt the solder directly with the welding gun, and the solder will quickly condense under the action of rosin, and the welding will be completed.