Advantages and main applications of FPC flexible circuits

Flexible circuits are designed to increase space utilization and product design flexibility to meet the design needs of smaller and higher density installations, as well as reduce assembly processes and increase reliability. It is the only solution that meets the miniaturization and motion requirements of electronic products.

A flexible circuit is a circuit that etches copper or prints a thick film circuit of a polymer on a substrate of a polymer. For thin, light, and compact devices, design solutions range from single-sided conductive traces to complex multi-layer 3D packages. The total mass and volume of the flexible package is reduced by 70% compared to the conventional wire harness method. Flexible circuits can also increase their strength by using reinforcing materials or liners to achieve additional mechanical stability.

Flexible circuits can be moved, bent, twisted without damaging the wires, and can have different shapes and special package sizes. Its only limitation is the volume problem. Thanks to its ability to withstand millions of dynamic bends, flexible circuits are ideal for continuous or regular motion in internal connection systems as part of the final product function. Some products that require electrical signal/power transfer and have a small form factor/package size benefit from flexible circuits.


Flexible circuits provide excellent electrical performance. A lower dielectric constant allows for fast transmission of electrical signals; good thermal performance makes components susceptible to temperature drops; higher glass transition temperatures or melting points allow the components to function well at higher temperatures.

Flexible circuits can provide higher assembly reliability and yield by reducing the hardware required for interconnections, such as solder joints, trunks, backplane traces, and cables commonly used in traditional electronic packages. Due to the assembly of conventional interconnect hardware consisting of multiple complex systems, high component misalignment rates are prone to occur. With the advent of quality engineering, thin and flexible systems are designed to be assembled in only one way, eliminating the human error typically associated with independent wiring engineering.

Early flexible circuits were mainly used in the field of connection between small or thin electronic products and rigid printed circuit boards. In the late 1970s, it was gradually applied to electronic products such as computers, digital cameras, inkjet printers, car stereo systems, optical drives (see Figure 10-1) and hard drives. Open a 35mm camera with 9 to 14 different flexible circuits. The only way to reduce the volume is to make the components smaller, the lines more precise, the pitches more compact, and the objects to be bendable. Cardiac pacemakers, medical equipment, cameras, hearing aids, laptops - almost all products today have flexible circ