What Do You Know About the Types and Processes of FPC Flexible Circuit Boards?

 FPC (Flexible Printed Circuit) is a printed circuit board made of polyimide or polyester film as the base material, featuring high wiring density, light weight, and thin thickness. It is mainly used in products such as mobile phones, tablets, medical devices, LEDs, automotive electronics, smart wearables, etc. FPC can be classified into single-sided FPC, double-sided FPC, multilayer FPC, and rigid-flex FPC.

Single-Sided FPC

It has a layer of conductive patterns formed by chemical etching, with the conductive layer being rolled copper foil. Insulating substrates can be polyimide, polyethylene terephthalate, aramid fiber ester, or polyvinyl chloride. Single-sided FPC is further divided into four subcategories:

  1. Single-Sided Connection without Cover Layer Conductive patterns are on the insulating substrate without a cover layer. Interconnection is achieved by soldering, fusion welding, or pressure welding.
  2. Single-Sided Connection with Cover Layer Similar to the non-covered type, but with a cover layer on the conductor surface. Pads are exposed during covering, typically with the end area left uncovered.
  3. Double-Sided Connection without Cover Layer Connection pads can be accessed from both the front and back of the conductor. A via hole is made in the insulating substrate at the pad position by punching, etching, or other mechanical methods.
  4. Double-Sided Connection with Cover Layer Different from the non-covered type, it has a cover layer with via holes, allowing termination on both sides while maintaining the cover layer. It consists of two layers of insulating material and one layer of metal conductors.

Double-Sided FPC

It has a layer of etched conductive patterns on both sides of the insulating base film, increasing the wiring density per unit area. Metallized holes connect the patterns on both sides of the insulating material to form conductive paths, meeting the design and functional requirements for flexibility. Cover films protect single/double-sided conductors and indicate component placement positions.

Multilayer FPC

It laminates three or more layers of single-sided/double-sided flexible circuits, forming metallized holes through drilling and electroplating to create conductive paths between layers—eliminating the need for complex welding processes. Advantages include light base film weight and excellent electrical properties. Multilayer FPC can be further categorized as:

  1. Flexible Insulating Substrate Products Manufactured on flexible insulating substrates, designed to be bendable. This structure typically bonds the two ends of multiple single/double-sided microstrip flexible FPCs, while the central part remains unbonded for high flexibility.
  2. Soft Insulating Substrate Products Manufactured on soft insulating substrates, without specified bendability.

Rigid-Flex FPC

It combines flexible and rigid circuit boards through lamination and other processes, forming a circuit board with both FPC and PCB characteristics. Rigid-flex boards integrate the flexibility of FPC and the rigidity of PCB, suitable for products with special requirements. They feature both bendable and rigid areas, significantly helping to save internal space, reduce product volume, and improve performance.

If you’re interested in FPC& PCB&PCBA products, pls kindly email to Sandy: sales9@hitechpcb.com



Comments

Post a Comment

Popular posts from this blog

How to solder the flexible PCB board?

  Before soldering, apply flux to the pad and treat it with a soldering iron to avoid poor tin plating or oxidation of the pad, resulting in poor soldering. Generally, the chip does not need to be processed. Use tweezers to carefully place the PQFP chip on the PCB board, taking care not to damage the pins. Make it aligned with the pad and ensure that the chip is placed in the correct direction. Adjust the temperature of the soldering iron to more than 300 degrees Celsius, dip a small amount of solder on the tip of the soldering iron, press down the aligned chip with a tool, and add a small amount of solder to the two diagonal pins. Hold down the chip and solder the pins on the two diagonal positions to make the chip fixed and unable to move. After soldering the opposite corners, recheck the alignment of the chip position. If necessary, adjust or remove and realign the position on the PCB board. When starting to solder all the pins, add solder to the tip of the soldering iron, and a...
Read more

How is the cost of SMT patch soldering calculated

The calculation of SMT patching prices is now almost transparent, and the algorithm for determining the cost per point is straightforward. However, it is first necessary to clarify the concept of "point". Different companies adopt varying algorithms, but for a PCB board, the total cost of SMT patching processing remains consistent. The core of SMT patching processing is to mount surface - mount components onto the solder pads of a PCB. Some companies count one solder pad as one point, while others consider two solder pads as one point. In this article, we take the example of calculating one point per solder pad. It only requires calculating all the solder pads on the PCB board. However, for some special components such as inductors, large capacitors, ICs, etc., additional calculations are needed. The specific empirical methods are as follows: for example, an inductor can be counted as 10 points, and an IC is calculated as half the number of pins (for example, a 40 - pin IC is...
Read more

How can we identify Integrated Circuits board and PCBA

  Inspect the surface of the PCB component body If a used  circuits board   part has been polished to make it look new, there may be tiny scratch patterns on the surface when observed under a magnifier. If it is covered up with paint on the surface, it will look bright and have no plastic texture. Inspect the printed text High-quality producers use laser printers to print the text silk-screen. It has a clear appearance, is non-conspicuous, and is difficult to erase. Typically, the text on refurbished chips is printed fuzzy and is not as sharp. You may find that the edges of the characters are blurred. The characters may be offset and the shades and colors may not be uniform. Moreover, many re-furbished chips use stencils for re-printing. In this case, if you feel the printed text, it should be easy to tell if it is new or refurbished. Inspect component pins If the component pins are shiny with a thin coating, then it may be refurbished. Original components are tin plated,...
Read more