What Is a Flexible Printed Circuit (FPC)? Get the Facts
Circuit boards are the building blocks of nearly all electronic devices. From computers and TVs to touchscreens, thermostats and digital watches, they are found in most electronic devices. As their name suggests, circuit boards are "boards" that feature one or more conductive paths known as a "circuit." Some electronic devices use rigid circuits, though, others use flexible printed circuits (FPCs).
The Definition of an FPC
An FPC is a type of circuit board that can bend without cracking, breaking or otherwise sustaining damage. They are distinguished from rigid circuit boards by their physical characteristics. Rigid circuit boards are stiff and rigid. FPCs, on the other hand, are flexible. Even if you bend an FPC, its conductive pathways will remain intact, so it will continue to function as intended.
How FPCs Are Made
You might be wondering how FPCs are made. There are many different types of FPCs, so there isn't a single universal manufacturing process for them. Nonetheless, all FPCs feature conductive traces printed on a substrate. The conductive traces typically consist of copper or a similar conductive ink. For the medium, polyimide may be used.
The Institute of Printed Circuits (IPC) has defined four variations of FPCs. Type 1 FPCs are made of a single layer that features insulating material on either one or both sides. Type 2 FPCs are made of two layers that are separated by an insulating material. They also have plated interconnect holes and provide access to the conductive traces on one or both sides.
Type 3 FPCs are made of three or more layers and feature an insulating material between their respective layers. They also feature plated interconnect holes and provide access to the conductive traces on one or both sides. Finally, Type 4 FPCs are made of two or more layers, which feature an insulating material between them. Unlike the other types of FPCs, they support a rigid printed circuit board.
