Issue link: https://iconnect007.uberflip.com/i/649323
38 The PCB Magazine • March 2016 culture. Very often, browsing through a web- site or brochure will leave the impression that a manufacturer provides a "full range of tech- nology"? Two-layer to 30-layer, .010" drill to microvias, standard materials to specialty ma- terials, quick-turn prototype through volume production. At the end of the day, no fabrica- tor wants to turn away business and they try to do their best to supply what their customers need. However, there will always be a technology level, material set, or delivery window that each shop excels at. Their yields are maximized, the corporate culture embraces the technology and lead-time, and ultimately prices are the most competitive. As an example, a supplier that ex- cels at building 4–8 layer standard technology likely runs with yields in the 97%+ range. But, if they were asked to build an 18-layer with blind and buried vias and via fill, the yields would drop dramatically. If the supplier that excels at building 18-layer blind and buried vias and via fill with yields in the high 90% range was asked to build a rigid-flex, yields would drop dramati- cally. When sourcing PCBs and creating a robust sourcing strategy, the challenge is identifying that sweet spot that maximizes a manufac- turer's yields and selecting the best group of suppliers to meet YOUR unique needs. Logi- cally, if a circuit board is being sourced with the supplier that is the best fit for that specific technology level, their yields are going to be maximized, pricing will be its most competitive and ultimately profits will be increased for the OEM and the fabricator. While this sounds like a simple concept, the implementation of this strategy takes time and resources that are not always available. Printed circuit board sourcing strategy: Are you guilty? Printed circuit boards are often one of the most expensive components of an assembly and arguably the most important due to their functionality and criticality. All too often, when time and resources are stretched too thin, these custom electronic components are purchased using the same strategy and structure as com- modity items. A PCB sourcing strategy might look like this: • Treated as a commodity versus a custom component • Procurement strategy is often made at a tactical, not strategic, level • Many are doing business with suppliers without a full understanding of the technical capabilities, capacity or financial situations of their suppliers • Static strategies in a dynamic market— this market is changing rapidly • The same strategy is used for domestic and off shore sourcing. One size fits all. This strategy can result in increased risk in terms of price stability and performance, in- creased risk of supply chain disruption and in- creased overall cost. Revamping your PCB strategy: Where do you start? You start with the basics. First review your PCB technology and volume requirements. Your requirements can then be segmented by attributes such as standard technology, HDI, heavy copper, flexible circuits, etc. Then search to match suppliers to these requirements. Au- dit the facilities. Don't hesitate to ask the tough questions to REALLY understand the type of work each supplier excels at. Next make sure that you have fully developed your procurement spec. Does it clearly spell out your requirements? Are any of your requirements adding unnecessary expense? It is not unusual to find that a corrective action implemented for an issue that happened 10 years ago is driving a re- quirement that increases cost and just isn't neces- sary in today's manufacturing environment. Case Study: Using a Strategic Sourcing Strategy Once a strong, diversified supplier matrix is put in place, analysis on large programs is sim- plified. To give an example, we were asked to assist with a pricing review and analysis of how to reduce cost on a specific project. This proj- ect included a set of PCBs with a wide spread of technology. One design was a simple two-layer design, another included microvias with cop- pCb sourCing? one size does not fit all