The process of PCB encapsulation has to do with the encapsulation or the filling of electronic assemblies using a compound to offer some protection from vibration and shock, contaminants like chemicals, moisture, and dust, and corrosion. The electronic process of plotting also ensures the protection of the components from any security threats like reverse engineering or tampering.
In contrast to conformal coating, PCB encapsulation is more robust and thicker, which helps in protecting the electronic assemblies from different tin whiskers and harsh environments.
What Does PCB Encapsulation Mean?
Another reliable method for offering protection to the PCBs from any external damage is referred to as PCB encapsulation. You can also call it PCB potting. From the name, encapsulation strives to surround your PCB rather than just adding coat to it. The casing or pot will be built over the printed circuit board and then the fluid will be poured in the casing, thereby sealing the PCB up.
Because they are two major component systems, the process of PCB plotting deals with the mixing of resin and the hardener. Doing this will create a form of chemical reaction, which creates the cross-linked polymer. In order to boost the performance, resin feature mineral fillers, which have greater viscosity. In addition, majority of resins are made to be VOC-free and cure only at room temperature. This is why, PCB coating sprays are not necessary.
Though it is possible to apply a casing of 0.5 mm, usually, they are much thicker than this. With an increase in thickness also comes a weight increase. This leads to higher expenses for each coating. Also, the components will get better protection as a result of the increase in thickness.
Pros
- Useful for high-volume applications
- Its dark color provides design security
- Provides greater protection against chock damage and water
Cons
- A significant increase in weight
- More process steps
- Costlier than the conformal coating
PCB Encapsulation vs Conformal Coating
Choosing between conformal coating and circuit board encapsulation isn’t about which method is best, rather it has to do with which of them suits your needs. Concerning this, you’ll consider:
- The layout and the design of the PCB
- Its individual components
- The Use environment’s expected conditions
If you’ll be exposing your device to very extreme conditions, choosing PCBA encapsulation will be a smart choice. This is because it provides additional protection benefits. These environments include power plants, mines, and manufacturing factories.
Moreover, if flexibility is the major goal, i.e. when dealing with consumer electronics, the better choice will be PCB coating. Electronic encapsulation has to do with offering protection to the electronic assembly using a compound as a form of defense from vibration and corrosion shock.
How to Perform PCB Encapsulation
PCB encapsulation or pcb plotting deals with sealing of the PCB in a thick resin layer that offers great protection from harmful chemicals and physical shock. This process enhances the PCB’s electrical performance.
To perform the PCB encapsulation,. You have to place your PCB assembly inside an open pot and then add some liquid compound in it till the entire PCBA becomes completely covered. This liquid has some hardener in it that helps to speed up the curing, and whenever this liquid solidifies, it plays a great protective role.
Normally, this resin utilized here is dark in color. This makes it very difficult for anyone to see that board under it. The materials commonly used for the plotting compounds include silicone, polyurethane, and pcb encapsulation epoxy.
Different materials come with their own benefits and pitfalls, which should be put into consideration. The applications determine your selection of the best material. For instance, pcb encapsulation epoxy and silicone work best for circumstances surrounding high temperatures. Moreover, urethane will offer a much better performance to chemicals. Therefo4e3, the most important point when choosing the materials is that you need to have a very good thought about the type of protection you desire.
When Should PCB Encapsulation be Used?
As already mentioned, PCB encapsulation provides great protection performance. Therefore if you want your application or device to be able to stand against abrasion, strong physical shocks, high temperature, chemicals, abrasion, as well as moisture, PCB encapsulation should be the next move. This is because it also includes the vibration damping option.
Also, PCB encapsulation can help in protecting engineering privacy. This is possible due to its colored resin. This makes it difficult for the other people around to see the underneath board region and then make some profit from it.
However, this is a two-edged sword because this invisibility can bring in some obstacles when there is need for a rework or repair. Also, potting is important for all high volume work because it can be handled quickly on any assembly line. Finally, PCB potting provides a great aegis against all electrical arcs. Therefore, if you have high-voltage electrical devices, we advice that you make use of circuit board encapsulation rather than conformal coating.
What are the Benefits of PCB Encapsulation?
- Encapsulation offers full protection against water damage and shock
- It provides a well-secure seal that prevents contaminants from entering
- It protects against chemicals and corrosion
- A very reliable way of reducing RFI/EMI interference in different devices
- Electronic components that are encapsulated provides a strong foundation for any wire bonding through the reduction of stress on the solder joints, which might have cause failure or breakage. This elimination of the exposed copper edges offers a reduced surface area for the oxidation. It also offers better adhesion between the solder pads and wires as well as better thermal performance.
- Encapsulation helps to protect against tin whiskers which are harmful, by creating a form of environmental barrier.
- It also prevents the components from getting destroyed or damaged because of external forces like mechanical vibration
- It ensures the best functionality of the device over time. Also, it improves the insulation found between the electrical devices to help in reducing the loss of current
- The reverse-engineer also finds encapsulated PCBs more difficult compared to those with conformal coating that are applied to some regions
- Also, it protects the components from experiencing thermal expansion problems. Furthermore, it retains iconic purity as well as properties relating to moisture resistance
- Generally, PCB encapsulation is faster and less expensive than the other methods of protection. This is because it needs few application steps and doesn’t need reassembling.
- VOC-free options are available
- Using the potting and encapsulation material is easy, even when using high-volume applications
What are the Applications of Encapsulation?
Encapsulation is applicable in different areas. These include photonics encapsulation as well as its use in cables.
PCB Encapsulation
Encapsulants are useful for protecting electronic components like PCBs that may experience damage as a result of moisture, mechanical vibration, as well as other environmental factors.
Offers Protection to Electronic and Electrical Components
Encapsulation provides protection for the electronic and electrical components from dust, dirt, water, as well as other contaminants.
Photonics Encapsulation
The encapsulated components are useful in applications including photonic integrated circuit, manufacturing of LEDs, solar panels, and fiber optics. Enclosures for optical instruments benefits from the utilization of electronic encapsulants. Also, they offer protection to the optical elements from any corrosion as well as prevent humidity and particles of dust from having any interference with the performance.
Also, LCDs require some defense against any light interference as a result of ultraviolet radiation. This is why they have to be encased in the encapsulant material. This helps in blocking UV rays coupled with maintaining a clear and a viewable surface area.
Cables
At times, the encapsulants are utilized on different electrical cables like twisted or coaxial pairs. They could get damaged easily due to oxidation and several environmental factors. Even, it protects the inner wires from exposure to moisture, chemicals, sunlight, or contaminants, as they could affect the performance.
What are the Required Materials for Encapsulation?
Materials involved in the process of circuit board encapsulation include adhesives, potting compounds, and resins. The resins usually coat the electronic devices during the electronic assembly. This helps in protecting them from environmental contaminants or water. You may need adhesives during the attachment of the encapsulating material that is found around the devices for protection.
This potting compound serves as an extra layer of protection for the electrical components. It also ensures heat dissipation through the conduction of excess thermal energy away. This prevents the extreme rise of temperatures beyond the normal range that can cause component failure.
Conclusion
One technology you must have if you wish to prolong your PCB’s lifetime as well as reduce repair cost is PCB encapsulation. However, there is a need for deep consideration when choosing the best technology for your PCB projects as conformal coating and potting are two complex processes. They are also full of variables, which may have an effect on the final cost. However, if you have some doubts, then there is a need to consult professionals in the field to help you out. They will have to consider all the aspect of the project, budget, application, turnaround time, etc. to be able to make the best choice for you.
