Flexible PCBs are made of Polyimide or a transparent polyester film. Also known as flex circuits or flex prints, they are best for high-temperature and high-density applications. These PCBs can take any desired shape. Moreover, they can flex while working without getting damaged.
Types of Flexible PCB
Based on requirements and operating conditions, there are 4 types of Flexible PCB.
Single-sided flexible PCBs.
It consists of a single conductor layer. This conductive layer rests on a flexible dielectric film. The components are connected only from one side of the PCB.
Double-sided flexible PCBs.
It consists of two-conductor layers on either side of a dielectric layer. Hence, giving the option to connect the components on either side of the PCB. This substrate provides the benefit of connecting intersects easily.
Multi-layer flexible PCBs.
It consists of three or more conductive layers. And these layers are separated using a dielectric. The thickness of the lamination is generally less in the area of bending. The irregular lamination provides higher flexibility to PCB.
Rigid- flexible PCBs.
It is a hybrid form that contains both rigid and Flex PCBs. It gives a higher component density as compared to others. And hence, these are a popular choice for daily commercial products.
Advantages of Flexible PCB
Flex PCBs require fewer interconnections. Which, in turn, reduces contact crimps and solder joints. It reduces the chances of PCB failure. Thus, improving reliability.
- Saves area.
Due to their tight bend capability, they require less space than rigid PCB boards. A Flex PCB fits in 10% of the area of a rigid PCB. This benefit finds Flex PCBs most suitable for military, medical and aerospace applications.
- Saves cost.
As Flex PCBs face fewer circuit failures. They also require less maintenance. So, in the long run, Flex PCBs are cheaper than rigid PCBs.
Now, let’s look at a project made on flexible PCB, ordered from PCBWay.
Flexible PCB Actuator
It consists of a rectangular flex-PCB. A controller varies the magnetic field of the PCB. So, when a magnet comes close to the PCB, it responds by flexing. It has twelve delta-connected coils.
It involves the interaction of magnetic fields of PCB and permanent magnet. At the first instant, the magnet attracts the PCB. While in the next, it repels it. If the time between these two instants is made small, the PCB appears to vibrate.
It’s a double-sided PCB with a gold finish. It is 0.13 mm thick and has excellent resistance to chemicals and UV radiation. The heat dissipation capacity is better and contains three through holes at the end of the PCB. The quality of the PCB is fantastic, which is visible in the image below.
**For more details on the above-discussed project, read Flexible PCB Actuator.