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August 2016 • SMT Magazine 51 for QFNs and LGAs. It is these latter two that are of greatest interest and value because they are well-suited to getting to a standard grid (e.g., 0.5 mm). Moreover, in a solderless assembly they require no solder on their terminations. Less manufacturing steps and the elimination of high-temperature excursions which can impact long term reliability are both good things. The common grid pitch simplifies design by mak- ing routing more predictable. When all three of the principles suggested are combined, well, the results are self-evident above. It needs to be conceded here that some components cannot be easily adapted to the concept in their pres- ent configurations, but they are what they are because there were no real physical constraints when they were introduced. In summary, it is possible to eliminate sol- der from numerous applications and mini- mize its use in countless others, and by doing so, enjoy significant benefits in design and manufacture. Not every company will be com- fortable without the training wheels. They will worry about falling and it can be argued they will be less nimble as a result. Yes, eliminating the "training wheels" from electronic assem- bly requires some risk-taking but it is through taking risks that progress is made. It is the combined discipline of design, procurement and manufacturing that will carry the day. From experience it can be found that a key guiding principle of excellence in manufactur- ing is to first do the right things and then do those things right. _____________________________________ P. Marc Carter Printed Circuit Engineer (Appendix) Those of us who deal with other aspects of electronic production realize how fortunate the printed circuit world is to have long-recog- nized, centralized re- sources like the Printed Circuits Handbook. The Handbook (and a few other consensus resources, like IPC) allow us to speak in a common language. Often as not, we ARGUE, but at least we argue from a common starting point. Historically, assembly and mi- croelectronics haven't enjoyed that same com- mon tongue. It is now a truly international business, and the shift of much of the fabrication base out of North America has resulted in (for an English-language resource of finite length at least) a necessary de-emphasis on fabrication details, and an increased emphasis on assem- bly, and securing printed circuit boards from remote sources. Another reviewer commented that an e-book that allowed the reader to fo- cus on those areas that were of particular inter- est in their case might be preferable. The only other way I can think of to deal with that is- sue would be a two-or three-volume PC Hand- book, each volume addressing the needs of a particular segment. SMT To read a book review by Karl Dietz, click here. References 1. Darren Smith may be reached by clicking here. THE AUTHORS OF THE PRINTED CIRCUITS HANDBOOK SPEAK

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