For the mobile market some PCB assemblies have been converted to flex circuit assemblies, in part because flex circuit assembly can be twisted or bent per the application needs.

Flex circuits offer the same advantages as conventional printed circuit boards: quality, reliability, and high density.

However, the most important attribute that has encouraged designers to opt for flex circuit technology is the capability of the flex circuit to assume three-dimensional configurations. Flex circuits can flex during installation, maintenance and use. A flex-circuit can save up to 70 percent of the space or weight of conventional wiring.

Assembly of components on flex involves a cleaning process, soldering process and handling process. Bending close to the edge of the component may cause solder joints to crack and subsequently cause open-circuit failures. This paper will provide recommendations on soldering and bending processes when components are mounted on a flex circuit.