Surface Mount Technology for High Reliability Telecoms Applications

The technology of printed circuit boards suitable for surface mount assembly is discussed with reference to solder mount tolerances and board finishing. Some design features which aid the production of reliable assemblies are described. The importance of preconditioning surface mount components with the soldering conditions to be utilised during the assembly process is emphasised. Some data which show the suitability of both SOIC and small PLCC packaged components, which have been vapour phase reflow soldered, are given. The reliability for long‐life applications of surface mount components and assemblies has not been demonstrated in general as yet and all manufacturers of such assemblies must validate their own assembly methods and components.