PCB News - Talking about the types and characteristics of FPC flexible circuit boards

Talking about the types and characteristics of FPC flexible circuit boards

Flexible Printed Circuit(FPC for short) is a highly reliable and excellent flexible printed circuit board made of polyimide or polyester film. It has the characteristics of high wiring density, light weight, thin thickness, and good bendability. At present, the mainstream FPC flexible circuit boards in the market are: single-sided, double-sided, multi-layer FPC flexible board and flexible-hard combined board. So what are the characteristics of these 4 kinds of applications in which neighborhoods, and then let me learn more about it with the editor.

1. The single-sided FPC flexible circuit board is the lowest cost, when the electrical performance is not high. When single-sided wiring, a single-sided FPC soft board should be used. It has a layer of chemically etched conductive patterns, and the conductive pattern layer on the surface of the flexible insulating substrate is a rolled copper foil. The insulating substrate may be polyimide, polyethylene terephthalate, aramid cellulose ester and polyvinyl chloride.

2. The double-sided FPC flexible circuit board is a conductive pattern made by etching on both sides of the insulating base film. The metallized hole connects the patterns on both sides of the insulating material to form a conductive path to meet the design and use function of flexibility. The cover film can protect single and double-sided wires and indicate where the components are placed.

3. Multi-layer FPC flexible circuit board is to laminate 3 or more layers of single-sided or double-sided FPC together, and form metallized holes by drilling and electroplating to form conductive paths between different layers. In this way, there is no need to use a complicated welding process. Multilayer circuits have huge functional differences in terms of higher reliability, better thermal conductivity and more convenient assembly performance. When designing the layout, the mutual influence of assembly size, number of layers and flexibility should be considered.

4. The traditional rigid-flex board is composed of rigid and flexible substrates selectively laminated together. The structure is compact, and the conductive connection is formed with metalized holes. If a circuit board has components on the front and back sides, FPC is a good choice. But if all the components are on one side, it will be more economical to choose a double-sided FPC and laminate a layer of FR4 reinforced material on its back.

5. The FPC flexible circuit board with mixed structure is a multi-layer board, and the conductive layer is composed of different metals. An 8-layer circuit board uses FR-4 as the inner layer medium and polyimide as the outer layer medium. Leads extend from three different directions of the main board, and each lead is made of a different metal. Constantan alloy, copper and gold are used as independent leads. This kind of hybrid structure is mostly used in the low temperature conditions where the relationship between electrical signal conversion and heat conversion and the electrical performance are relatively harsh, and it is the only feasible solution.

I hope this reveal can provide you with reference and help. Welcome new and old customers all over the country to inquire. Our engineers will answer your confusion in PCB circuit board production and processing one by one. Welcome new and old customers to visit the factory.