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76 The PCB Magazine • December 2016 tools and concurrent engineering are primary drivers of this phenomena. What we have not learned to do in this era is to develop an effec- tive technique to feedback manufacturing ex- periences and wisdom. The data flow is all one direction, from design to manufacturing. The Opportunity of Design for Manufacturing (DFM/A) There are five compelling reasons that pre- dictive engineering is essential to the design of electronic products: 1. Products have become increasingly com- plex. Not only must products meet increased expectations from customers but they must be environmentally friendly, energy efficient and conservative of resources. All of this must be done in ever shrinking product life cycles. 2. Minimizing cost is imperative. DFM/A has been shown in benchmarking and case studies to reduce assembly costs by 35% [1] and PWB costs by 25% [2] . 3. 75% of the manufacturing cost of a prod- uct is determined by all the design drawings and specifications. 4. In the electronic product design process, 60% of the manufacturing cost is determined in the first stages of design when only 35% of the design cost has been expended. As shown in Figure 1, the product definition process in- cludes specifications and partitioning. This is a technology tradeoff analysis (the balance of loss and gain in various domains' performance ver- sus costs). 5. Finally, a common language needs to be established that links manufacturing to design and R&D. This common language defines pro- ducibility as an intrinsic characteristic of a de- sign. It is not an inspection milestone conduct- ed by manufacturing. Producibility scores form a non-opinionated basis that allows for a team approach that results in a quality, cost-compet- itive product. The Nature of the Problem Current practice is that design data travels in only one direction—towards manufacturing. As shown in Figure 2, there is no provision for the capabilities, experiences and wisdom gained in manufacturing to flow back to the design envi- ronment. Hence, many companies use concur- rent engineering to bring experienced manufac- turing personnel into the design process, to try and impart some of that wisdom. Unfortunate- ly, these experienced manufacturing people are getting rarer and it takes far too long to gain that experience. The difficulties don't just end there, most of the time the manufacturer is far, far away. Under the best of circumstances, the wisdom and experience must be imparted as opinion. And opinions are difficult to defend. This might be a working solution for small, vertically integrated companies with vast ex- perience in manufacturing. But in the last UNDERSTANDING PREDICTIVE ENGINEERING Figure 1: Predictive engineering contains more than just 'density modeling'; it provides caution on 'failure-prone components' and 'suitability for test,' as well as optimizing electrical performance and minimizing signal integrity problems. Figure 2: Current product data movement.