In many cases, small connectors are reflow soldered.

Connector manufacturers will inform you of the temperature conditions for reflow soldering through product samples. When reflow soldering is performed, please confirm the temperature conditions and other contents.

Temperature conditions can be divided into four stages according to the temperature setting.

1. Temperature rise section

In this stage, the solvent contained in the flux evaporates and the temperature rises.

Be careful not to increase the temperature sharply. Otherwise, the solvent will boil, resulting in solder balls (※1) and gaps (※2).

2. Preheating section

In this stage, the temperature is uniformed to avoid temperature deviation of parts and activate the flux.

3. Formal heating section

In this stage, the PC board and the mounted parts are heated evenly, the activation state of the flux is promoted, and the solder is heated to the melting temperature of the solder.

Be careful not to increase the temperature sharply. Otherwise, gaps will be generated.

On the other hand, if the temperature rises too slowly, the humidity of the solder will decrease.

Be careful not to keep it in a high temperature state for a long time. Otherwise, the resin will partially melt or deform.

4. Cooling section

Air cooling is used in this stage.

Note: Please cool quickly. If cooling is slow, the welding strength may be weakened.

◼Solder balls: Spherical agglomerations on solder. They will splash to other contacts and cause short circuits.

◼Gap generation: Bubbles are generated inside the solder. They will weaken the welding strength.

◼Solder creeping phenomenon: The phenomenon of solder climbing onto the connector terminals. It will reduce the welding strength and cause poor conduction.

◼Overlap welding: The phenomenon of welding adjacent terminals