Advantages and Disadvantages of Flexible PCB

Advantages

1. Flexibility

A significant advantage of using a flexible PCB is that it can be more easily routed and connected in three-dimensional space, and can also be rolled or folded for use. As long as it is curled within the allowable radius of curvature, it can withstand thousands to tens of thousands of uses without damage.

2. Reduce Size

In the assembly and connection of components, compared with the use of conductive cables, the conductor cross-section of the flexible PCB is thin and flat, which reduces the wire size and can be formed along the casing, making the structure of the device more compact and reasonable, reducing the installation and connection volume. Compared with rigid PCB, space can be saved by 60~90%.

3. Reduce Weight

In the same volume, the weight of the flexible PCB can be reduced by about 70% compared with the wire and cable under the same current carrying capacity, and the weight can be reduced by about 90% compared with the rigid PCB.

4. Consistency of Installation And Connection

Assembled and connected with flexible PCB, eliminating the error when wiring with wire and cable. As long as the processing drawings are proofread and passed, all the winding circuits produced in the future are the same. There will be no misconnection when installing the cable.

5. Increased Reliability

When the flexible PCB is used for installation and connection, because the wiring can be made on the X, Y, and Z planes, the transfer interconnection is reduced, the reliability of the whole system is increased, and the inspection of faults is convenient.

6. Controllability of Electrical Parameter Design

According to the requirements of use, designers can control capacitance, inductance, characteristic impedance, delay and attenuation, when designing flexible PCBs. Can be designed to have the characteristics of a transmission line. Because these parameters are related to wire width, thickness, spacing, insulation thickness, dielectric constant, loss tangent. This is difficult to achieve when using wire and cable.

7. The end can be soldered as a whole.

Like rigid PCBs, flexible PCBs have terminal pads, which can eliminate wire stripping and tinning, thus saving costs. The terminal pads are connected with components, devices, and plugs. Dip soldering or wave soldering can be used to replace the manual soldering of each wire.

8. The Use of Materials Can Be Selected

Flexible PCB can be manufactured with different base materials according to different usage requirements. For example, in assembly applications requiring low cost, polyester film can be used. In demanding applications where superior performance is required, polyimide films can be used.

9. Low Cost

The use of flexible PCB assembly can reduce the total cost. This is because:

1) Due to the consistency of various parameters of the wires of the flexible PCB, the implementation of the overall termination eliminates the mistakes and rework that often occur when the cable wires are installed and connected, and the replacement of the flexible PCB is more convenient.

2) The application of flexible PCB simplifies the structural design, it can be directly attached to the component, reducing the clip and its fixing parts.

3) For wires that need to be shielded, the price of flexible PCB is lower.

10. Continuity of Processing

Since the flexible foil clad board can be continuously supplied in rolls, the continuous production of flexible PCBs can be realized. This also helps reduce costs.

Disadvantages

1. High One-Time Initial Cost

Because flexible PCBs are designed and manufactured for special applications, the initial circuit design, wiring, and photographic negatives are expensive. Unless there is a special need to apply a flexible PCB, it is usually best not to use it in a small amount of applications.

2. Difficult to Change And Repair Flexible PCBs

Once the flexible PCB is made, it must be changed from the base map or the compiled light drawing program, so it is not easy to change. The surface is covered with a protective film, which must be removed before repairing and restored after repairing, which is a more difficult task.

3. Limited Size

Flexible PCBs are usually manufactured by batch process when they are not yet common. Therefore, due to the limitation of the size of production equipment, they cannot be made very long and wide.

4. Improper operation is easy to damage

Improper operation of the installation and connection personnel can easily cause damage to the flexible circuit, and its soldering and rework need to be operated by trained personnel.