Issue link: https://iconnect007.uberflip.com/i/327747
20 The PCB Design Magazine • June 2014 duction partner and that partner has just let you down. You could leave in a huff and start find- ing a new partner, but that's more time wasted and you would be even further from production with no greater assurance of success. This is why selecting a vendor for an FPC requirement is a contract negotiation and part- ner-selection, and not just a price comparison. In most cases, the Number 1 factor in choos- ing an FPC source is delivery and the reliability of same. Piece part cost may seem important at the negotiating table but your production line will shut down if you don't get the FPC you need for your assembly. FPC is usually the start- ing point in product manufacture, so regardless of its cost position on the BOM, and it is usually a trivial cost item, if the FPC isn't at your fac- tory you will produce nothing. At this point the FPC will assume major importance: Remember the old adage, "For want of a nail the shoe was lost...." Tiny problems can stop big enterprises! The only way to choose between vendors is by history (i.e., past performance). The negoti- ating chatter may be about NREs, tooling and lot charges, but in the back of the (knowledge- able) buyer's mind the big issue is: if he says four weeks, will I see parts by the end of June? And if he doesn't deliver, what do I do? You can stare cold-eyed at the IGF salesman, trying to read his intentions, but your best guide is how IGF performed in the past. Do they recover quickly from disaster? Do they have the necessary mate- rials on hand, ready to re-release to the factory? And so forth. Repeat orders and High-Volume Production You might expect that custom manufacture is used only for prototypes, but since there are almost no catalog FPCs, it is the rule in the FPC universe. A second order should run much more WHY PRoCURINg FLExIBLE PRINTED CIRCUITRY IS DIFFERENT continues feature Figure 5: rigid-flex circuitry provides the most space and weight efficient interconnection. This circuit has five rigid terminal areas with plated through-hole interconnections. Black material along the rigid edges is semi-hard and gives strain relief.