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JULY 2021 I SMT007 MAGAZINE 27 down from one engineer to the next or from company to company without understanding the true impact on product life. In lieu of expensive GUESS testing, many now utilize the Spock approach to product life assurance. is approach consists of the ship- ping clerk (or some other duly ordained per- sonnel) raising their right hand, parting their middle two fingers, and speaking the words, "Live long and prosper" just as the product leaves the shipping dock. Predictions of Life How long will it live? Answering that ques- tion when product designs, supply chains, and components used are constantly in flux (pun intended) can cause more stress to the engineers than the product itself and can con- tribute to a reduction of their life. Taking the time and spending the money to truly under- stand the factors that affect product life is challenging to say the least. Life predictions, aer all, are just that—predictions. Astrol- ogers and Tarot card readers make predic- tions as well, and it is important to weigh the data obtained from accelerated stress testing accordingly. SMT007 Bob Neves is chairman/CTO of Microtek China, and vice chair of the board at IPC. Reliable AOI methods have become powerful, economical complements to tra- ditional test strategies. AOI can be used successfully as a process monitoring tool for measuring printing, placement, and reflow performance. Some advantages include: Detecting and correcting SMT defects during process monitoring is less expen- sive than after final test and inspection, where repairs are typically 5 to 10 times more costly. Detect trends in process behavior, such as placement drift or incorrect mount- ing, earlier in the overall process. Without early inspection, more boards with the same defect could be rejected during functional test and final inspection. Identify missing, skewed, or misplaced components with incorrect polarity earlier in the assembly process when component placement is verified before reflowing. Yet, a single inspection system has limitations, especially when there is limited or no communication with the balance of the line. In this setup, it simply cannot opti- mize a printed circuit board assembly process. Equipment suppliers must cooperate to achieve communication for a zero-defect future. M2M connectivity can optimize the process by exchanging real-time SPI and AOI mea- surement data with other machines in the production line. This real-time feedback includes measurement data such as offset, volume, height, area, and warnings to other systems, while analyzing trends to optimize the pro- cess and identify trends. The connected systems can automatically define correlations between the processes. To read the rest of this chapter and more, download The Printed Circuit Assembler's Guide to SMT Inspection free here. EXCERPT: The Printed Circuit Assembler's Guide to... SMT Inspection: Today, Tomorrow, and Beyond Chapter 5: Advanced Process Control and Inspection