Flexible circuit board
1. Single panel
After the completion of the circuit, a single PI copper coated material is covered with a protective film to form a flexible circuit board with only one conductor.
2. Ordinary double sided panels
After using double sided PI board and copper clad material to complete the double-sided circuit board, a protective film is added on each side to form a circuit board with double conductor.
3. The generation of one side cardboard
In the circuit board manufacturing process, pure copper foil material is used to add a protective film on both sides of the circuit, making it a circuit board with only one conductor, but the conductor is exposed on both sides of the circuit board.
4. Double sided Committee
Using two layers of single-sided PI tundish copper material and glue, open the window to become a local texture in a specific position, and separate the structure with a two layer double-sided conductor circuit board to achieve area circuit board area and high bending performance.
advantages and benefits of flexible circuit boards
Flexibility and reliability of flexible circuit boards
Four types of flexible PCB are currently popular: single side, double side, multi-layer and rigid flexible combination. "The cost of a single-sided flexible panel is the lowest," Friedman said. when the electrical performance is not high and single side wiring can be adopted, the single side flexible plate should be adopted. this most common form has been used in business, such as printers. Ink jet cartridge and computer memory. the single side flexible plate has a conductive pattern etched by chemical etching, and the conductive pattern layer on the surface of the flexible insulating substrate is a coil of copper foil. the insulating substrates for flexible assembly can be polyimide (Kapton), polyethylene terephthalate (PET), aramid fiber paper (Nomex) and polyvinyl chloride (PVC).
The double-sided flexible plate is a conductive pattern made by etching one layer on both sides of the basement membrane. the metallized holes connect the patterns on both sides of the insulating material to form a conductive channel to meet
The flexible design and use functions. the cover protects single and double sided wires and indicates the placement of the components.
The multilayer flexible plate is a single-sided flexible circuit board or a double-sided flexible circuit board. The three layers or layers are stacked together to form a metallized hole through drilling and electroplating, forming a conductive path between different layers. this eliminates the need for complicated welding processes. although this flexible type of conductive layer can be designed indefinitely, in the design layout, in order to ensure the convenience of assembly, the interaction Between assembly dimension, layer number and flexibility should be considered.
Traditional rigid flexible plates are selectively overlapped by rigid and flexible substrates. compact structure and conductive connection with metallized holes. Considering reliability and price, manufacturers should try to reduce the number of layers.
the flexible circuit board industry is experiencing a small and rapid development. Polymer thick film process (PTFs) is an efficient and low-cost method for PCB production. the process is to selectively screen conductive polymer inks on inexpensive Flexible substrates. A typical flexible substrate is pet. pTF conductors include screen printed metal fillers or toner fillers. pTF itself is clean and uses lead-free SMT adhesive without etching.
There is also a mixed structure flexible circuit board, which is also a multilayer board, but the conductive layer of the multilayer board is made of different metals. this hybrid structure is mostly used in the relationship between electrical signal conversion and thermal conversion, and its electrical performance is relatively harsh. In this case, the flexible hybrid circuit is the only feasible solution.
whether the structure of these flexible circuit boards can save cost and get the best use can be assessed by convenience and total cost of interconnection design. "The whole way of interconnection is different. Mobile phones are a form of block layout. laptop is a XY location layout. The printer is a rigid curved PCB. These products are made of different materials with different prices to reduce the cost of each interconnection. each design must have type assessment to get the best performance price ratio.
2、 Economy of flexible circuit board
If the circuit design is relatively simple, the total volume is small, and the space is suitable, most of the traditional interconnection methods are more cost-effective. if the circuit is more complex, the signal is more processed, or has special electrical or mechanical performance requirements, flexible circuit board is a better design option. compared with rigid materials, flexible materials also have a potential cost saving reason, that is, they do not need connectors.
the high cost of raw materials is the main reason for the high price of flexible PCB. although its raw materials are more expensive and manufactured more troublesome, DiPalermo believes that folding, bending and multi-layer jigsaw functions will reduce the size of the overall components, reduce the use of materials, and reduce the overall assembly cost.
Three, the cost of flexible PCB is being further reduced.
Despite the above cost factors, the price of flexible assembly is falling, and is getting closer to the traditional PCB. this is mainly due to the introduction of new materials, improvements in production processes and structural changes. in one Example, the use of acrylic adhesive is cancelled in rigid bending plate assemblies with many layers.
Because of the thinner copper layer, some new materials now have finer lines. thinner copper layers make components lighter and lighter, and thinner assembly makes flexible components more suitable for smaller space. in the past, we rolled the copper foil into glued media. Today, copper foil can be produced directly on a medium without the need for an adhesive. these technologies can obtain copper layers of several microns, enabling the industry to obtain 3 nanoclines or a narrower width. when the adhesive is removed from the flexible circuit board, the flexible circuit board has flame retardancy.
This can speed up the UL authentication process and further reduce it.