Have you ever questioned how the everyday electronic items you use can resist adverse weather conditions, such as extreme temperatures and humidity? PCB potting and conformal coating are two popular techniques used to protect electronic devices from these harsh conditions, but which one should you choose?
In this blog post, we probe differences between PCB potting and conformal coating. Likewise, we’ll discuss the advantages and disadvantages of each method. We hope you get your project going by giving expert tips to help you weigh the pros and cons. So sit back, and prepare to learn more about PCB potting vs. conformal coating!
PCB Potting Vs. Conformal Coating: Material Differences
The materials used in each of these methods impact the performance and durability of the finished product. Here are the focal differences:
Potting materials are typically made from thermosetting plastics. They’re mixed with hardeners to create a rigid, durable material. Conversely, conformal coatings are usually made from silicones, acrylics, or urethanes, which remain flexible after application.
Potting materials are usually applied as a liquid poured into a mold or enclosure and allowed to harden. Conformal coatings are used as a liquid sprayed or brushed onto the surface of the PCB.
Materials for potting create a hard, protective shell around the PCB. Conformal coating materials are designed to be flexible and conform to the contours of the board.
Thicker layers are possible using Potting materials. Meanwhile, conformal coating materials preserve better against environmental hazards such as moisture and vibration.
Generally more expensive: potting materials. Conformal coatings are cheaper.
Impact on Electronics
Potting materials can provide stronger physical protection against direct impact than conformal coatings. However, if not applied properly, potting can obstruct the electrical device’s functionality.
Typically, Conformal coatings adhere better to the surface of the PCB than potting materials.
Now that we’re done with that, we’ll delve deeper into the specific processes.
What Processes are Involved in Potting Vs. Conformal Coating?
When talking about processes, both techniques are quite distinct. Each has distinctive features that make it appropriate for particular applications. Here’s a breakdown of the processes involved in each method:
PCB Potting Process
- The first step in PCB potting involves mixing and preparing the potting compound. This compound is typically a two-part epoxy resin that is combined together in a specific ratio.
- Once the potting compound is prepared, the PCB is put on a mold, and the potting mix is poured over the PCB. The potting compound then encapsulates the entire PCB, including the components.
- After the potting compound has been applied, it needs to cure. The curing process allows the compound to harden and bond to the PCB. This could take a couple of days or just a few hours.
Conformal Coating Process
- Before conformal coating can be applied, the PCB must be cleaned thoroughly to remove dirt or debris. This is typically done using a solvent or cleaning agent.
- Once the PCB is clean, it’s time to mask. Cover (mask off) any areas that should not be coated. This may include connectors, switches, or other sensitive components.
- The conformal coating is then applied to the PCB using a spray, brush, or dip coating process. This coating is often a thin layer of substance that fits the PCB and its components’ shapes.
- Lastly, after applying the conformal coating, it needs to cure. This involves allowing the coating to dry and harden. Depending on the kind of coating employed, the curing process might last anywhere from a few hours to a number of days.
As you can see, the processes involved in PCB potting and conformal coating are quite different. Potting incorporates encapsulation of the entire PCB in a compound. In contrast, conformal coating applies a thin material layer to the PCB’s surface.
You should know better what to expect from each process now.
Relevant Factors for Choosing
What factors are relevant to your choice of method application?
Before you apply either potting or conformal coating on your product, here are the most noteworthy elements to consider:
PCB potting provides a complete treatment of the PCB, including components, while conformal coating only covers the surface of the PCB. This means that potting offers a higher level of protection against environmental factors like moisture, dust, and vibrations.
Conformal coating is more flexible than potting, which means it can withstand more movement and vibration without cracking. Because of this, it is a preferable option for applications where the PCB will be subject to flexing or movement.
Is it repairable?
Conformal coating is easier to remove and reapply than potting, making it a better choice if repairs or modifications are likely to be needed.
Conformal coating can be applied in a thinner layer than potting, which makes it a better choice for more complex PCBs with tight spaces between components.
Conformal coating is generally less expensive than potting, especially for small-scale production runs.
Conformal coating can be applied quickly and easily, while potting requires more time and effort to apply and cure.
Ultimately, when you choose a method, you should cater to the specific needs of your device/application.
In the next sections, we’ll look closer at the pros and cons of PCB potting and conformal coating, so you will finally decide.
What Does PCB Potting Have Over Conformal Coating?
Let’s specifically talk about the advantages of PCB potting over conformal coating. Potting offers a variety of benefits that make it the best choice for electronic devices that need care against dampness and other environmental dangers.
Firstly, potting offers a higher degree of protection compared to conformal coating. It “encapsulates” the electronic component, ensuring it is fully protected from contaminants affecting its performance. With conformal coating, this level of defense is not achievable.
Secondly, PCB potting is more durable than conformal coating. Potting materials are usually made of tough materials like silicone and polyurethane, which offer superior protection against impact and mechanical stress. These materials can withstand high temperatures and extreme environmental conditions, ensuring that your electronic components are protected from damage for a long time.
Thirdly, potting provides superior electrical insulation. The potting materials used in PCB potting have high electrical resistance and are non-conductive, so they can effectively isolate electronic components from each other, reducing the risk of short circuits.
Fourthly, PCB potting provides better heat dissipation than conformal coating. The potting materials are good conductors of heat, which helps dissipate heat generated by the electronic components, reducing the risk of overheating and prolonging the device’s lifespan.
Lastly, potting can improve the aesthetics of the electronic device. Potting materials can be colored or clear and give your electronic device a sleek, professional look, making it more attractive and marketable.
Conformal Coating Advantages
What Does Conformal Coating Have Over PCB Potting?
In the previous section, we’ve already talked about the advantages of PCB potting over conformal coating. But what about the other way around? What does conformal coating have over PCB potting?
First of all, conformal coating is much easier to apply than potting. Unlike potting, which requires a complex and time-consuming process, the conformal coating can be sprayed or brushed onto the PCB surface. This means that conformal coating is the way to go if you’re looking for a quick and simple solution to protect your PCBs.
Another advantage of conformal coating is that it allows for speedier rework and repair. Since conformal coatings are typically thinner than potting compounds, they can be easily removed with solvents or other methods, allowing easy access to the PCB underneath. (It’s much easier to repair or modify a PCB that has been conformally coated, thinking about it.)
Additionally, conformal coatings are often more flexible than potting compounds, making them a better choice for applications where the PCB is subjected to vibration or other mechanical stress. The flexibility of the coating allows it to move with the PCB, reducing the risk of cracking or further damage.
Finally, conformal coatings can be more cost-effective than potting compounds, especially for large-scale production runs. Since the process is simpler and requires less material, using conformal coating can be a more economical solution for protecting your PCBs.
When NOT to Use PCB Potting
Here are some instances when it’s best not to use PCB potting:
- When the electronic component has a high power rating – it may cause the potting material to overheat and damage the component.
- Suppose the electronic component generates a lot of heat, such as a power transistor or a voltage regulator. In that case, the potting material may not be able to dissipate the heat efficiently and may cause the component to fail.
- Instances where the electronic component needs to be easily replaceable – Potting material is difficult to remove. It may damage the component during removal, making it challenging to replace or repair.
- When the electronic component is sensitive to moisture or humidity – material for potting may trap moisture and cause corrosion, leading to component failure.
- Frequent adjustments or tuning need to be made – Potting material can make it difficult to access and adjust the component.
Lastly, assess the electronic component’s specifications and requirements before deciding whether to use PCB potting. If the component meets the criteria, potting protects from mechanical damage, vibration, and environmental factors. But if it doesn’t, don’t force it.
When NOT to Use Conformal Coating
Now, here are some instances when you may not want to use conformal coating:
- When you need to access components frequently – Since conformal coating creates a barrier, it can be tricky to access and service components once they are covered. This can make repairs or upgrades more challenging and time-consuming.
- When you have components with high power dissipation – Conformal coating can insulate components and prevent them from dissipating heat effectively, leading to overheating and component failure. In this case, using a different cooling method may be better.
- When you have components that require frequent adjustment -Similar to the first point, conformal coating can make it challenging to adjust components such as trim pots or potentiometers. This is because you would need to remove the coating first before making any adjustments, which can be time-consuming and risky.
- When you have components that require exposure to air – Certain components may require exposure to air to function properly, such as some types of sensors or microphones. Conformal coating can prevent this exposure and negatively impact their performance.
- When you have components sensitive to solvents – Conformal coating is typically applied using solvents, which can damage or interfere with certain components. If so, you might have to choose an alternative method or find a solvent-free conformal coating option.
Now, whether to put on conformal coating in your PCB or not? It’s imperative to take into account these aspects. While it can provide protection and other benefits, the method may not be the best at the moment.
Choosing Based on Factors
How to Decide Which One to Choose – It’s Up to You!
Still undecided? Here are expert tips professionals use to discern what’s best.
Identify your priorities
What’s your main concern when it comes to protecting your PCBs? Is it cost, durability, ease of application, or something else? By understanding what you value most, you can narrow down your options.
Consider your resources
Do you have the equipment and resources needed for potting or conformal coating? If not, which option is more accessible to you?
Ponder about your end objective
What is the end use of your PCBs? Will they be exposed to harsh environments, or will they be used in a more controlled setting? Understanding the final application of your board can help you conclude.
Evaluate the risks
What are the potential risks associated with each method? Are there any safety concerns or hazards to the functionality of your PCBs? Understanding the risks goes a long way in deciding.
Test and evaluate
Finally, try both methods and evaluate the results. Sometimes, the only real way to tell which approach is ideal for you is to give it a shot. Check to see if it firs the circumstances of your intentions.
Consult with experts
If you need aid in determining which method is best for your specific application, feel free to seek guidance from experts in the field. They could present insightful guidance that will aid in your recourse.
Where to Get Expert PCB Services and Advice
As we mentioned earlier, seeking guidance from masters in the field is crucial when deciding which method to use for your PCB application. That’s where we come in.
With years over 15 years of experience in electronics, we have the resources to help you make a great decision based on what you need. Whether you want to pot or conformal coat your PCB, we can provide valuable insights and recommendations.
At PCBMay, we understand that every application is unique and requires a tailored solution. Because of this, we communicate closely with our clients to determine what’s special about their needs.
In addition to our expertise, we do offer a wide range of high-quality materials and equipment to ensure your PCB is protected and performs at its best. So if you’re considering potting or conformal coating for your PCB, don’t hesitate to contact us. We’re always prepped to assist your electronic needs.