Today we introduce the three main characteristics of FPC flexible circuit board:
Flexibility and reliability of 1.FPC flexible circuit board
At present, there are four kinds of FPC: one side, two sides, multi-layer flexible plate and rigid flexible plate.
One side of the flexible plate is the lowest cost, when the electrical performance requirements are not high on the printed board. In the single side wiring, should choose one side flexible plate. It has a layer of conductive pattern etching the conductive pattern layer in the flexible insulating substrate surface for rolled copper foil. The insulating substrate may be polyimide, polyethylene terephthalate, aramid fiber ester and polyvinyl chloride.
The double flexible board is on both sides of the base insulating film layer made of conductive pattern etching. The metal hole is connected with the insulating material on both sides of the graph to form a conductive path, in order to meet the flexibility of the design and use function. The covering film can protect the single and double wire and indicate the position of the component.
The multilayer flexible plate is a single-sided or double-sided flexible printed circuit laminate 3 or more layers together, through boreholes L, electroplating forming hole metallization, conductive paths formed in different layers. In this way, it is not necessary to use complex welding process. Multilayer circuits have a great difference in the higher reliability, better thermal conductivity and more convenient assembly performance. In the design of the layout, it should take into account the interaction between the assembly size, the number of layers and the flexibility.
The traditional rigid plate is made of rigid and flexible substrates are pressed together to form the stratum. Compact structure, forming a conductive connection with metal alone L. If a printing plate, opposite has element, rigid flexible plate is a good choice. But if all the components are on the side of the case, the use of double-sided flexible plate, and on the back of a layer of laminate FR4 reinforced materials, will be more economical.
The convenience degree and the total cost of the design can be evaluated in order to achieve the best performance price ratio.
The economy of FPC flexible circuit board
If the circuit design is relatively simple, the total volume is small, and the space is suitable, the traditional way of the inside connection is much cheaper. If the circuit is complex, processing many signals or have special electrical or mechanical performance requirements, the flexible circuit is a good design choice. When the size and performance of the application beyond the capacity of the rigid circuit, flexible assembly is the most economical way. A thin film can be made into a 12mil bonding pad with 5MIL through hole and a flexible circuit for 3mil lines and spacing.
Flexible circuit industry is in a small but rapid development. Polymer thick film method especially suitable for equipment control panel. In mobile phones and other portable products, polymer thick film method is suitable for the conversion of components, switches and lighting devices on printed circuit boards into polymer thick film circuit. Both to save costs, but also to reduce energy consumption.
Generally speaking, the flexible circuit is larger than the cost of the rigid circuit, and the cost is higher. In the manufacture of flexible plates, many situations have to face the fact that many of the parameters are beyond the tolerance range. The difficulty of making flexible circuits lies in the flexibility of the material.
Cost of FPC flexible circuit board
Now the structure makes the product more thermal stability, there is very little material does not match. Some of the newer materials can make more precise lines because of the thinner copper layer, which makes the assembly more lightweight and more suitable for smaller spaces. In the past, the rolling process of copper foil with adhesive in the coating adhesion to the medium, now can not use directly generated on the medium copper foil adhesive. Remove the flexible circuit after some adhesives with flame retardant properties. This can not only accelerate the uL certification process can further reduce costs. Flexible printed circuit board solder mask and other surface coatings to reduce the cost of flexible assembly.
In the next few years, the smaller, more complex and more assembled FPC flexible circuit boards will require more innovative methods of assembly, and the need to increase the hybrid flexible circuit. The challenge for flexible circuit industry is to use its technological advantages to keep in sync with the computer, telecommunications, consumer demand and active market. In addition, the flexible circuit will play an important role in lead free operation.