Design Economics of Surface Mount PCBs

This paper presents an experience in designing a printed circuit board prototype as part of a general surface mount investigation for commercial electronics application. The point of view is that of a low volume assembler of relatively large, complex PC boards which use standard components. Three prototype versions were designed using different criteria. FR‐4 substrate was used for all of the designs. A comparison of the three designs with the through‐hole version indicates that the economic success of surface mounted printed circuit assemblies is heavily dependent on the physical design of the printed circuit board. Some of the aspects of a surface mounted circuit assembly that are discussed include design philosophy and tools, printed circuit board fabrication and bare board test. Design practices that would ideally utilise the small size of surface mount components are contrasted with those practices necessary to provide low cost and manufacturability of the printed circuit board.