Flexible Circuits     Flexible Circuits are a rapidly growing application of printed wiring technology.  Flexible circuits are most commonly used for connections to moveable objects like printer heads.  However, many applications do not require the multiple flex capability of these expensive devices. Eddy Electronics offers flexible circuits as both the high performance product on laminates such as Kapton, or lower cost flex circuits, ideal for prototypes on less expensive laminates.  The choice of laminates is growing with the number of applications that require flex. Very often, a flex circuit is specified to replace wiring or cables which would require more space.  Flex circuits also offer design options, and when coupled with  multilayer processes, impedance can be controlled and components can be located anywhere a designer wishes. In large or complex systems involving multiple printed circuits, the whole system can be designed as one panel with individual boards connected through flexible segments.  This is refered to as flex-rigid technology.  In this kind of application, the whole product may be folded up and installed with a minimum of confusion or interferance.  This has been employed in the newest night vision equipment and the Mars-Probe lander. The two types of flexible circuit here are actually very different.  The brown coloured one is a more common multiple flex type. Reliable but expensive. The green one is for a consumer product in which it had to flex only for installation and involves flexible soldermask as well as laminate.  This was less expensive, however, some of the materials' properties require some compromise in temperature resistance and multiple flexibility.