How important is it to use the correct conformal coating?

Choosing the right conformal coating material means selection of the right conformal coating for:

  1. the printed circuit board (PCB) in the field for its long term reliability and
  2. the correct conformal coating application method giving a cost effective method without affecting the performance of the conformal coating to protect the PCB.

For example, application of a UV cure conformal coating can be extremely effective. It gives an instantaneous cure and offers fantastic moisture and chemical protection.

However, a specialist UV conveyor and UV lamps is required for curing the conformal coating. Therefore, the cost of the system must be considered against the process performance.

Also, repair of UV conformal coating material is difficult and may be a consideration.

Another example would be using a water based conformal coating.

This solvent free conformal coating material provides an extremely safe environment for operators.

However, the method for application and the curing of the conformal coating needs to be considered since it can be extremely difficult to apply, take a significant amount of time to cure and work in progress may be affected.

Nexus discuss the choice of the right material as the Holistic approach to conformal coating.

When you consider these three points you have to balance them to create the best compromise solution that suits your requirements.