A PCB, or printed circuit board, connects and powers electronics large and small. These components are delicate and need to be protected accordingly. Here’s your guide to conformal coating for PCB’s.
Choosing the Best Coating
Your primary concern in deciding which conformal coating to choose for a PCB is the future functionality of the board. You’ll want to examine durability, chemical resistance, and immunity to temperature. There are various styles and application processes to choose from. We’ll take a look at three:
Silicone: Silicone is flexible and can withstand an extensive temperature range. If you have a PCB that needs to fit into a small area, this is not an excellent choice as it has a thicker application.
Acrylic: This choice is right for reworking the covering with a simple drying process. Because of its low chemical resistance acrylic is not a good choice for PCB’s exposed to a harsh environment.
Parylene: Parylene is chosen for its ability to cover surfaces uniformly no matter the shape. It also is applied in a manner that keeps it very thin yet smooth and secure. While parylene is the most protective coating, it is not easy to rework.
Your choice of coating for a PCB will come down to what environment exposure the board will have and what level of protection you require from the conformal coating.
How to Protect a PCB
The two conformal coating types are liquid and parylene. Each can be applied to PCB’s but the impact of use should be considered when making a decision between them.
Liquid: PCB’s can be brushed, dipped, or sprayed with a liquid coating for protection. It’s efficient, easy, and inexpensive but can result in gaps if the topography is irregular.
Parylene: Once a gas, this coating can be sprayed onto a PCB and be sprayed to cover all areas no matter the shape. Parylene coating tends to be more expensive.
To learn more about what conformal coating will be right for your project, contact us today!