Introduction to the differences between single-sided FPC, double-sided FPC, and multi-layer FPC

Single sided FPC flexible circuit boards have only one layer of chemically etched conductive patterns, which are made of calendered copper foil material. The insulating substrate can be polyimide, polyethylene terephthalate, aramid fiber ester, and polyvinyl chloride.

Single sided FPCs can be divided into four sub categories: 

1 Single sided connection without covering layer;

2 Single side connection with covering layer;

3. Double sided connection without covering layer;

4. Double sided connection with covering layer.



The double-sided FPC flexible circuit board is a conductive pattern etched on both sides of the insulating substrate film, increasing the wiring density per unit area. The metallized hole connects the patterns on both sides of the insulating material to form a conductive path to meet the design and use functions of flexibility. The covering film can protect single and double sided wires and indicate the location of the component.



Multilayer FPC flexible circuit boards are made by pressing three or more layers of single or double sided flexible circuits together, forming metallized holes through drilling and electroplating, and forming conductive paths between different layers. Multilayer FPC circuit boards have significant functional differences in terms of higher reliability, better thermal conductivity, and more convenient assembly performance.