The flexible circuit board is a highly reliable, excellent flexible printed circuit board made of polyimide or polyester film as a substrate. Abbreviation, soft board or FPC, has a characteristic of high wiring density, light weight, thin thickness and bending.
1 Introduction
Mainly used in mobile phones, laptops, PDAs, digital cameras, LCMs, etc.

2 prenatal processing
In the production process, in order to prevent excessive long-term excessive, there is a problem of excessive low or decrease the process of drilling, calendering, cutting, and the problem, and evaluate how to choose from customers. Best effect of flexible circuit board. Preferred pretreatment is particularly important.
Prenatal pretreatment, there are three aspects of the treatment, and these three aspects are completed by the engineers. The first is the FPC board engineering assessment, mainly whether the customer's FPC board can produce, whether the company's production capacity can meet the customer's board requirements and unit costs; if the engineering assessment passes, then you need to prepare it immediately, meet each production link The raw materials supply, finally, the engineer is handled: the customer's CAD structural map, the Gerber line data and other project documents are handled to suit the production environment and production specifications of the production equipment, and then the production drawings and MI (engineering process card) are put to Production and civil control, procurement and other departments enter the routine production process.

3 production process
Double-panel
→ Post cover film → Supplement → Curing → Sink Nickel Gold → Printing Character → Shear → Electric Test → Digital → Entrance Examination → Packaging → Shipping
Single-sided panel
Cut → Entry Experience → Packaging → Shipping

4 characteristics
⒈ Short: Assembly
All lines are all configured. Provincial access to excess cables
FPC board
⒉ Small: Volume is smaller than PCB
Can effectively reduce product volume. Adding the convenience of carrying
⒊ ⒊: Weight is light than PCB (hard board)
Can reduce the weight of the final product
4 thin: thickness than PCB thin
Can improve softness. Strengthen the assembly of three-degree space in the refined space

5 application
mobile phone mobile telephone
Heavy weight and thin thickness of the flexible circuit board. It can effectively save product volume, easy to connect the battery, microphone, and button.

Use the integrated line configuration of the flexible circuit board, and thin thickness. Transfer the digital signal into the screen, and the liquid crystal screen is presented
CD Walkman
The three-degree space assembly characteristics and thin thickness of the flexible circuit board. Put the huge CD into a good companion carrying
Disker
Regardless of the hard disk or soft disc, it relies very much from the high softness of the FPC and the ultra-thin thickness of 0.1mm, and completes fast reading information. Whether it is a PC or Notebook.
Latest use
Elements of Suspension Circuits (SU Yin Ensi.n Cireuit) and XE Packaging Boards of Hard Drive (HDD, HARD Disk Drive)
Wireless charging coil array, focusing electromagnetic concentration in a certain area, reducing space transfer consumption, thereby increasing electrical energy conversion efficiency.

6 basic structure
Copper foil: Basically divided into electrolytic copper and translucent copper. Common in thickness is 1OZ 1 / 2OZ and 1/3 oz
Substrate film: Common thickness is 1 mIL and 1/2 mils.
Glue (Etume): The thickness is determined according to customer requirements.
Cover Film
Covered film protective film: Surface insulation. The common thickness has 1 mil and 1 / 2mil.
Glue (Etume): The thickness is determined according to customer requirements.
Release paper: Avoiding the effectors in front of the pressure; facilitate operation.
Pi Stiffener Film
Reinforcement board: reinforcing the mechanical strength of the FPC, facilitates surface mounted operation. The common thickness has 3 mils to 9 mils.
Glue (Etume): The thickness is determined according to customer requirements.
Release paper: Avoid the adhesive to be accepted before pressing.
EMI: Electromagnetic shielding film, the inner line of the protection circuit board is not interfered by the outside (strong electromagnetic zone or susceptible area).

7 advantages and disadvantages
Advantages of multi-layer circuit boards: high assembly density, small size, light quality, due to high density assembly, components (including components) reduced, thereby increasing reliability; increased wiring layers, then adding design flexibility; It is also possible to constitute the impedance of the circuit, and a certain high-speed transmission circuit can be formed, and the circuit, the electromagnetic shielding layer can be set, and the metal core layer can be installed to meet the function and demand of special thermal insulation; convenient installation, high reliability.
The shortcomings of multi-layer PCB boards (unqualified): high cost, long cycle; high reliability test methods. Multi-layer printed circuits are electronics, multi-function, high speeds, and small volumes of mass. With the development of electronic technology, especially the wide application of large-scale and large-scale integrated circuits, the multi-layer printed circuit density is high, high precision, and high-altitude change direction.

8fpc patch points
The process of FPC surface SMT requires a lot of differences from traditional hardboard PCB SMT solutions. To do FPC SMT processes, the most important thing is to position. Because the hardness of the FPC board is not enough, it is soft. If the dedicated carrier is not used, the fixed and transmission cannot be completed, and the basic SMT process such as printing, patching, oververts cannot be complete. [2]

9 development prospects
The FPC will continue to innovate from four aspects in the future, mainly:
1, thickness. The thickness of the FPC must be more flexible and must be thinner;
2, and the ability to resist. It can be bent is FPC and the child, and the future FPC varies must be stronger and must exceed 10,000 times.