Dry goods attack! What is the function of conformal coating on soft plate?

PCB manufacturers, PCB designers and PCBA processors will explain dry goods for you! What is the function of conformal coating on soft plate?

Flexible Printed Circuit (FPC), also known as Flexible circuit board and flexible circuit board, is favored for its light weight, thin thICkness, free bending and folding and other excellent characteristics. However, the quality inspection of FPC in China mainly depends on manual visual inspection, with high cost and low efficiency. With the rapid development of the electronic industry, the circuit board design tends to be more and more high-precision and high-density, and the traditional manual detection methods can no longer meet the production needs. Automatic detection of FPC defects has become an inevitable trend of industrial development.

Because the soft and hard bonding boards are the combination of FPC and PCB, the production of soft and hard bonding boards should have both FPC production equipment and PCB production equipment. First, the electronic engineers draw the lines and shapes of the flexible bonding boards according to the needs, and then distribute them to the factories that can produce the flexible bonding boards. The CAM engineers process and plan the relevant documents, and then arrange the FPC and PCB production lines needed for FPC production line to produce PCBs. After the two types of soft boards and hard boards come out, the FPC and PCB are seamlessly pressed through the press according to the planning requirements of the electronic engineers, After a series of details, the soft and hard combination board is finally made. A very important link, because the hard and soft bonding plates are difficult and have many details, it is generally necessary to carry out a full inspection before shipment, because its value is relatively high, so as to avoid the loss of relevant interests between the supply and demand parties.

Conformal coating is very necessary for soft board and soft board patch which must work in harsh environment. It can protect the circuit board from corrosion, moisture and dust, extend the shelf life of electronic products, and ensure the performance and reliability of electronic products. Today, let's take a look at the protective effect of conformal layer on soft boards.

For harsh environments, conformal coatings should be optimized to better adapt to extreme environments. The following protective measures should be technically optimized: conformal coating shielding, electrostatic elimination and film thickness measurement.

Conformal coating shield

Now, some parts of the soft board that do not need conformal coating should be covered, so that unnecessary parts (such as circuit board bracket, potentiometer, switch, power resistor, connector) will not be sprayed with conformal coating to stop abnormal signals.

In the process of conformal coating implementation, masking tape is usually used for conformal coating shielding. In order to meet the different shapes of different parts in the shielding, the shielding tape is cut into different shapes and sizes. Due to its shortcomings, the method is prone to cause quality problems, including low efficiency, electrostatic generation and excessive gel residues that are difficult to eliminate.

Optimization measures

3M tape should replace traditional tape. The cutting method should be from cutting with tools to using special cutting tools, because the special cutting tools can determine and cut different shapes according to the shape, volume and size of the shield. As long as the protective cover is covered with unnecessary parts, conformal coating will not be applied to it.

Conformal coating thickness measurement

The soft plate surface is coated with conformal coating, which is a thin and light film with a thickness of only a few microns. This film can effectively isolate the circuit board surface from the environment and prevent the circuit from being eroded by chEMIcals, water and other pollutants.

Therefore, the reliability of the circuit board will be greatly improved, the safety factor will be strengthened, and the shelf life will be guaranteed for a long time. However, due to the non-uniformity of the coating, the protective function of conformal coating is still unclear. Therefore, both the soft board and the final product will fail, especially in harsh environments.

How to maintain long-term stability in harsh environments is a very important issue in the manufacture and application of electronIC components. Therefore, technicians must take necessary protective measures to ensure the normal operation of electronic products in harsh environments. PCB manufacturers, PCB designers and PCBA processors will explain dry goods for you! What is the function of conformal coating on soft plate?