Issue link: https://iconnect007.uberflip.com/i/1007258
58 FLEX007 MAGAZINE I JULY 2018 Can you relate to this? You are tackling your first flexible circuit design. It is a simple circuit, with just two layers. Lines and space are gen- erous, the hole size isn't pushing any limits, and this seems like a perfect design to cut your teeth on. You do your research, complete the layout, send the design package in for a quotation and then place the order, confident in the process. There are a few engineering questions related to materials, and you make a note for future applications: Be more specific about the cov- erlay requirements and whether flexible solder mask or film-based coverlay is needed. Things are going smoothly. The circuits are delivered, assembled, installed right on sched- ule. But something isn't working. Now the fun begins—troubleshooting. Where do you start? After the painful process is complete, you discover that one of the components was too heavy and bulky for the flexible circuit to support without reinforcement and traces had been broken during installation. A quick rede- sign adds a rigidized stiffener, the circuits are ordered again, and the project moves forward. In my experience through the years, when first working with flexible circuits or rigid-flex cir- cuits, this is a learning curve that everyone goes through. With this learning curve in mind, I reached out to customers and industry friends to ask them to share some of their first experiences with flex, "gotcha" moments and advice for those new to flexible circuit design. A few com- mon themes stood out. Materials Material selection is critical in some designs, especially dynamically flexing applications, and anecdotal information tells the story that the options available are more complicated than one would anticipate when first work - Flex Talk by Tara Dunn, OMNI PCB The Learning Curve: Your First Flex Circuit