PCB, which is a printed circuit board, is often referred to as a hard board. It is the supporting body of electronic components and is a very important electronic component. PCB generally USES FR4 as the base material, also known as hard board, can not be bent, flexure. PCB is generally used in some places that do not need to bend and have relatively hard strength, such as computer motherboard, mobile phone motherboard, etc.
FPC is actually a kind of PCB, but it is quite different from the traditional printed circuit board. It is called soft board, known as the flexural circuit board. FPC generally USES PI as the base material, which is a flexible material and can be bent and flexural at will. FPC normally requires repeated flexing and linking of widgets, but that’s not all. Smartphones are now thinking about flexure prevention, which requires FPC as a key technology.

In fact, FPC is not only a circuit board that can bend, but also an important way to design a three-dimensional circuit structure that can be combined with other electronic products to build a variety of different applications. Therefore, from this point of view, FPC and PCB are very different.

For PCB, the circuit board is generally flat unless the circuit is made into a three-dimensional form by means of film glue. Therefore, to make full use of three-dimensional space, FPC is a good solution. In the case of hardboard, the current common space extension scheme is to use slot and interface card, but FPC can make a similar structure as long as the transfer design, and the directional design is also more flexible. With one piece connected to the FPC, two pieces of hardboard can be connected into a set of parallel wiring systems, or can be turned into any Angle to adapt to different product appearance design.

FPC can, of course, use terminal connection for wire connection, but it can also use hard and soft boards to avoid these connection mechanisms. A single FPC can configure and connect many hard boards using the layout. This approach reduces the connector and terminal interference, can improve the signal quality and product reliability. The figure shows the soft and hard board of multi-chip PCB and FPC architecture.