FPC (Flex Printed Circuit) refers to flexible printed circuit boards, also known as flexible circuit boards or flexible electronic circuits. FPC is a circuit board based on polyimide film, which is flexible, thin, light and foldable, and is widely used in electronic products. FasTechCircuit will provide a detailed introduction to the structure, manufacturing process, and application of FPC.

1、 Structure of FPC
The structure of FPC is mainly composed of polyimide film, copper foil, wire, covering layer, etc. Among them, polyimide film is the main structure of FPC, which is a polymer material based on polyimide. Polyimide film has excellent mechanical strength, high temperature stability and electrical insulation properties, and can withstand the effects of high temperature, high voltage and other environments. Copper foil is the conductive layer of FPC, used to make wires and circuit graphics for circuit boards. The wire is an FPC circuit made of copper foil, used to connect various electronic components and sensors. The covering layer is the protective layer of FPC, used to protect the surface of FPC from mechanical damage and chemical corrosion.

2、 Manufacturing process of FPC
The manufacturing process of FPC mainly includes steps such as copper foil preparation, printing, etching, drilling, film application, and pressing.
Copper foil preparation: Process the original copper material into copper foil with a thickness of 18um to 105um.
Printing: printing circuit graphics onto polyimide film to form circuit graphics.
Etching: Etching off unwanted copper foil to form circuit wires.
Drilling: Drilling is used to connect wires from different layers or connect circuit boards and components. Drilling is done after printing and etching.
Film application: Apply a covering layer to the surface of the circuit board to protect it.
Pressing: Press the various parts of the FPC together to form the final FPC.

FPC can be divided into various types: single-sided FPC, double-sided FPC, multi-layer FPC, and rigid flexible combination FPC

1、 Single sided FPC
Single sided FPC means that the copper foil printed on the polyimide film has only one side and the other side is polyimide film. Single sided FPC has the advantages of simple structure, simple manufacturing process, and low cost. Single sided FPC is usually used for some simple circuits, such as LED light strips, battery connections, etc.

2、 Double sided FPC
The double-sided FPC refers to that the copper foil printed on the polyimide film has two sides, and the other side is the polyimide film. Double sided FPC has the advantages of double-sided conductivity, high density, and suitability for various complex circuits. Double sided FPC is usually used to connect lightweight electronic components, handheld devices, LCD displays, PCB boards, etc.

3、 Multilayer FPC
Multilayer FPC refers to a complex circuit board made by stacking multiple copper foil layers on a polyimide film. Multilayer FPC has the advantages of high density, high reliability, and suitability for complex circuits. Multi layer FPCs are commonly used in high-end electronic products, such as smartphones, tablets, laptops, etc.

4、 Rigidity and flexibility combined with FPC
The combination of rigid and flexible FPC refers to the combination of hard boards and flexible circuit boards to form a flexible and rigid circuit board. The combination of rigid and flexible FPC has the advantages of combining rigidity and flexibility, and is suitable for complex circuits. The combination of rigid and flexible FPC is commonly used in fields such as automotive electronics, medical devices, and aerospace.

5、 Blind hole FPC
Blind hole FPC refers to drilling holes on a printed circuit board that do not penetrate the entire board thickness and only form holes inside one layer. This type of hole is also known as blind hole. Blind hole FPC has the characteristics of high density, compactness, and space saving. Blind hole FPCs are commonly used in high-end electronic products, such as smartphones, tablets, etc.

6、 Buried hole FPC
Buried hole FPC refers to drilling holes on a printed circuit board, but not throughout the entire board thickness, but forming holes between different layers, which are also known as buried holes. Buried hole FPC has the characteristics of high density, compactness, and space saving. Buried hole FPCs are commonly used in high-end electronic products, such as smartphones, tablets, etc.

7、 SMD FPC
SMD FPC refers to the direct soldering of surface mounted components onto the FPC without the need for connecting wires and sockets. SMD FPC has the characteristics of high density, high-speed transmission, and suitability for miniaturization design. SMD FPC is commonly used in fields such as mobile communication, consumer electronics, and automotive electronics.

8、 Flexible LED display screen FPC
Flexible LED display screen FPC is a flexible LED display screen made by combining LED beads and FPC. Flexible LED display screen FPC has the characteristics of flexibility, foldability, curlability, and portability. Flexible LED display screen FPC is commonly used in fields such as billboards, stage backgrounds, and outdoor advertising.

9、 FPCA
FPCA (Flexible Printed Circuit Assembly) refers to the combination of FPC and SMT (Surface Mount Technology) components