Sitting in almost every device — from consumer devices like smartphones, tablets and wearables to specialised industrial technology — are printed circuit boards (PCBs). 

Although PCBs are used for many applications, one crucial consistency is that they must be designed with some form of protection against their surrounding environment. Coming up against moisture, vibration, thermal shock and contamination, the protection of PCBs is instrumental to the lifespan of an electronic device… 

Plus, as companies and customers are increasingly focusing on electrical waste (and manufacturers aim to meet net-zero environmental commitments), improving the durability of electronic products is more important than ever. 

So, what are the most common protection methods, and how can electronics manufacturers decide which is most suitable for each project?

Potting and encapsulation

Potting and encapsulation are two standard techniques for protecting sensitive electronic components such as PCBs, automotive or avionic equipment and cable joint assemblies. 

Both techniques involve the submersion of an electronic component in a resinous material. Potting creates a shell (or pot) around the PCB and its parts by encasing it in poured resin, whereas encapsulation is when a component is dipped into a resin mould and coated.   

As the resin hardens, the components are removed from the mould to be placed in the assembly. Although they are very similar methods, one subtle difference between encapsulation and potting is that the mould is not part of the final product.  

The coating is set — either by air drying, oven drying or curing with UV light — to protect the PCB against potential damage. 

When deciding on the types of compounds used to encapsulate the electronic components, manufacturers must consider the risk factors and level of protection required…  

Silicone coating offers high flexibility and resistance to water, chemicals and UV light damage. For those looking for a less costly protective coating, epoxy is a good choice — harder than silicone and resistant to temperatures up to 200 degrees, yet often brittle at low temperatures. 

Urethanes are well suited for low-temperature environments but do not offer the same level of resistance to harsh chemicals and high temperatures provided by silicone and epoxy coatings. This difference in temperature resistance is a critical consideration for some components, as heat-sensitive electronic components could be damaged by compounds that require heat curing. 

Additionally, electronics manufacturers must consider the thickness and weight of the coating to ensure the protection does not interfere with any other product specifications. In some cases, manufacturers might opt for conformal coating instead. 

 

Conformal coating 

Conformal coating is a lightweight alternative to potting and encapsulation.  

This is an ideal solution if you require PCBs with a precise thickness to be fitted into smaller devices, and dipping, brushing or spraying conformal coatings to PCBs are the main methods for manufacturers. 

Like potting and encapsulation, the compounds chosen depend on the product’s scope. 

Silicone and acrylic offer all-around protection and high flexibility at a reasonable price — but silicone only has moderate humidity resistance, and acrylic has limited chemical resistance. 

Polyurethane coatings, however, are highly flexible and durable, with strong resistance to harsh chemicals and environmental conditions. 

No matter which type of coating is used, proper application is the most critical factor.  

Whether manufacturers choose potting and encapsulation or conformal coating for their PCBs, nothing will sufficiently protect them if not done to a high standard — running the risk of system damage and failure… 

 

Leave it to the experts

Many businesses employ the help of electronics manufacturing specialists to ensure they are developing intrinsically safe products.  

As a proud subsidiary division of EC Electronics, Swan EMS can offer potting, encapsulation and conformal coating services to our customers. 

With nearly 40 years of experience in the electronics industry, EC Electronics has the knowledge and expertise to support even the most complex electronics projects for clients across the globe — with a specialist facility to ensure all services for PCBs, connectors and interface box assemblies meet exceptionally high standards.  

Thanks to EC Electronics’ fully trained operators, skilled in assembling a wide range of incredibly complex boards and working to industry standard IPC-A-610 Class 3, you can rest assured your project is in safe hands.  

EC Electronics, Swan EMS’ parent company, provides specialist potting, encapsulation and PCB conformal coating services for various industries and applications. To discuss your next PCB project, please get in touch with our friendly customer service team at  info@swanems.co.uk or call 01495 320 989.