Classification-of-fpc-flexible circuit board

At present, the flexible circuit board mainly has one - sided, two - sided, multi - layer and the new flexible circuit board.

The single surface flexible plate is the lowest cost, when the performance is not high.In the single - sided wiring, the single - sided flexible plate should be used.It has a layer of chemical etching, the conductive graphics layer on the flexible insulation substrate is the copper foil.The insulating substrate can be polyimide, polyethylene terephthalate, aromatic amide fiber ester and polyvinyl chloride.

Two - sided flexible plate is a conductive pattern which is etched on both sides of the insulating basement membrane.The metal holes connect the two surfaces of the insulating materials to form conductive paths to meet flexural design and function.The cover film can protect the single, double-sided lead and indicate the position of the element.

The multi-layer flexible plate is a single or two-sided flexible circuit layer that is pressed together, which can form the conductive path between different layers by drilling and forming the metal hole.This requires no complicated welding process.Multilayer circuits have great functional differences in higher reliability, better thermal conductivity and more convenient assembly performance.When designing the layout, consideration should be given to the interaction between the size of the assembly, the number of layers and the flexibility.

The traditional rigid flexible plate is composed of rigid and flexible substrate with selective formation pressure.The structure is close, and the conductive connection is formed by metallization of the steel.If a printing plate is positive and negative, the rigid flexible plate is a good choice.But if all the components are on one side, it will be more economical to use both sides of the flexible plate and press the FR4 reinforcement on its back layer.

The flexible circuit board of mixed structure is a kind of multilayer board, and the conductive layer is composed of different metals.An 8-layer plate USES fr-4 as the medium in the inner layer, and the polyimide is used as the outer medium to extend the lead from three different directions of the motherboard, each of which is made of different metals.Copper alloy, copper and gold are respectively independent leads.This hybrid structure is the only feasible solution in the case of the relationship between electrical signal conversion and heat transfer and the more severe low temperature.

It can be evaluated by the convenience and total cost of internal design to achieve the best performance ratio.