Flexible Circuits Vs. Printed Circuit Board

It is not uncommon for many designers and engineers to think of a versatile circuit as a printed circuit board (PCB) that can bend. While it is true that a flex circuit and PCB perform the identical electrical function, the structural and mechanical differences are important, and never understanding them can result in poor yields and field failures. It will be important to note the completely different terminologies which can be used in the electronics business. Flexible circuits have been called flex, flex circuits, versatile pcbs and versatile printed circuit boards. Printed circuit boards will also be referred to as PCB’s or just hardboards. Let’s start by stating the plain difference: a flexible circuit can bend, fold and twist, a printed circuit board can't. This key distinction requires a flex to be manufactured with a unique set of materials, design rules and different manufacturing processes. If you have any inquiries relating to exactly where and how to use pcb assembly (www.cakeresume.com), you can speak to us at our site. Perhaps the largest distinction is the supplies. Both printed circuit boards and flexible circuits have similar construction: Within the case of a single sided circuit, the development is dielectric base layer, adhesive layer; copper or conductive materials layer and maybe a protecting overlay materials. For a printed circuit board the base layer tends to be rigid and often contains glass reinforcement, FR4 is probably the most typical material. This provides the fabric glorious dimensional stability, thermal resistance and mechanical strength, however little or no capability to bend. Flexible circuit base materials are most commonly made from polyimide. The material has excellent flexibility properties, but it surely doesn't have the same mechanical support for components and is less dimensionally stable vs. Since printed circuit boards don’t flex, the requirements on the adhesives are restricted to chemical and thermal properties. Then again, a versatile circuit has an additional requirement to permit bending. An adhesive that works effectively for a hard board, would crack or fracture in a flex utility. An adhesive for a versatile circuit must "stretch" a bit. The result is that an adhesive for a flex will have totally different thermal, chemical and mechanical properties from adhesives used in PCBs. There are two basic sorts of copper movie, Electro Deposited (ED) and Rolled Annealed (RA). The key distinction is that RA copper is way more versatile. Is required in dynamic flex functions. ED copper does have some flexibility and may be used in some circumstances, and is sort of completely used to supply rigid pcb’s. There can also be a HDED (high ductility) copper that is electro-deposited with a remedy that makes it more versatile, however not quite nearly as good as RA. Considerations for copper are seldom a difficulty for a rigid printed circuit board since it doesn’t require flexing. Copper selection in a versatile circuit can be essential to efficiency, both in dynamic flexing and flex to install applications. The before mentioned material differences create a whole set of added complexities in design and fabrication of a versatile circuit. Registration tolerances, chemical and thermal properties and a host of different elements mean design specifications for a flex will be totally different vs. The important thing differences mentioned in this blog pertain to widespread constructions in flexible and exhausting board circuits. Both are available in alternate materials for particular purposes. Most notably, versatile circuits can be found in adhesiveless constructions.