Why Conformal Coating
Conformal Coating is a protective non conductive dielectric layerthat is applied onto the printed circuit board assembly to protect theelectronic assembly from damage due to contamination, salt spray,moisture, fungus, dust and corrosion caused by harsh or extremeenvironments.
It is usually used in products that are used in outdoor environmentswhere heat and moisture are prevalent. Coating also prevents damagefrom rough handling, installation, reduction of mechanical and thermalstress. It also prolong the life of the product during its operation.At the same time, it helps to increase the dielectric strength betweenconductors enabling the design of the PCB to be more compact and ***all.It also acts to protect circuitry and components from abrasion andsolvents.
When coated, it is clearly visible as a clear and shiny material.Some coatings are hard, while others h***e a slightly rubbery texture.Most coatings include a marker that appears greenish white when viewunder UV light. This marker enables easy inspection of the coatingthoroughness checking during production.
In the past, coatings are only applied to military and life/medicalproducts as the cost and the process of doing this was high then. Inrecent years, the development in material and new processes has enabledc***umer electronics products to be coated as well. This will bebecoming more common and will become a norm as circuitry and electroniccomponents continue to shrink in size and dimension.
Conformal coating started as a simple process performed onelectronic substrates in need of extra protection from externalelements, with little attention paid to quality factors beyond adequatecomponent coverage. The increased capability of semiconductorassemblies to perform complex tasks in automotive applicati***,
trafficcontrol, signage, outdoor surveillance, and mission-critical elementshas increased the demand for conformal coating. Because device failurecould h***e dire c***equences, the quality of coating materialapplication is critical. New equipment and processes are in place toaccommodate the conformal coating requirements of these emergingtechnologies. A ***ooth transition to automated precision conformalcoating can be achieved through an analysis of the product being coatedand the desired result, the coating material used, the processselected, and of the economic costs over a period of time.