Conformal coatings are thin protective layers applied to printed circuits or other electronic substrates. They provide environmental and mechanical protection to significantly extend the life of the components and circuitry. Conformal coatings are traditionally applied by dipping, spraying or flow coating.
Why Use Conformal Coating
Electronic assemblies that are exposed to harsh environments such as marine, geothermal and other outdoor or corrosive environments are susceptible to an accelerated rate of contamination during normal use because of the environment they operate in. These types of assemblies are usually coated as standard practise.
Many modern electronic assemblies are so tightly packed with components that the spaces between the conductors are greatly reduced. These tightly packed components are susceptible to an accelerated rate of contamination during normal use simply because of the close proximity of the conductors. These types of assemblies can benefit from conformal coating extending their expected service life.
What Does the Conformal Coating Do?
Particles that settle onto electronic modules during production, testing or alternately as contamination that occurs during normal operation, can contact and span two or more closely spaced conductors, resulting in a short circuit. This can lead to potentially serious electrical failures. Despite efforts to keep electronic assemblies clean and free from contaminants, the possibility that stray particles, metal shavings, dust, and dirt will be present exists. Conformal coating provides a layer of electrical insulation preventing contact between physical contaminants and conductive features on PCB modules.
Moisture and corrosive vapours over time may result in corrosion of metals in PCB assemblies. Though conformal coatings are not hermetic and thus do not seal electronics from moisture and solvent vapours, they do act as barriers to slow diffusion of moisture and corrosive vapours through the polymer before reaching electronics.
Biological contaminants such as fungus may also lead to degradation of PCB assemblies. Conformal coatings help to protect electronics from biological contaminants.
With a wide range of Conformal Coatings available, all with different features and benefits, it is important that the correct coating and method of application be chosen. The main areas to be addressed when choosing which conformal coating to use include: environment factors, electrical requirements, board layout, method of application and the ease of rework and repair.
In today’s busy and cost conscious environment, the reliability of electronic equipment is a major issue. In most cases the application of a conformal coating, either during manufacture or as a retrofit solution can contribute to significant maintenance cost reductions.
Contact us today for an obligation free estimate and coating plan tailored to suit your particular application.