New Application of Reflow Technology in Double Side Through-hole PCB Assembly

With the rapid development of Surface Mount Technology,the reflow-soldering technique be- comes more and more important.It is also being used in the traditional through-hole PCB assembly.Reflow soldering technique basically takes the advantage of heat radiation,convection and conduction to warm up the mounted parts,solder paste and PCB,weld the solder paste,then cool them down to firmly solder the compo- nents on the PCB.So far,most of the ESM suppliers have not adopted this technology to the through-hole type PCB assembly yet.With the emergence of new electronics product designs,some of the double sides through- hole PCB cannot be assembled by wave soldering any more.Though some ESM suppliers have tried this tech- nology to double sides through-hole PCB assembly,a solder coating layer was generated on the components (especially for connector with long golden-plated pins),reducing the reliability of the products.This paper presents an innovate solution to soldering of through-hole parts with long pins with the reflow technology.