Friday, June 03, 2011

Will conformal coating help prevent ESD?

Yes and no. It will help prevent direct ESD to the components which are protected by the coating. However the coating itself can become charged and can induce high voltages on the pcb. This can give ESD when a connector pin or other exposed conductive part makes contact with another conductor. The energy in this type of ESD is quite high and is a risk to any component through which the ESD current may flow on the pcb. Modules in plastic enclosures can also suffer this risk. Also, the conformal coating gives no protection against external electrostatic fields which can have the same effect as charge on the coating.

Of course the overall risk of damage occurring is difficult to predict.


Gershman Israel said...

As far as I know the thickness of the coating is not equal and usually thin on vertical leads. In this places the edges might even be exposed and not coated at all. I believe these exposed placed could be hit by ESD. I would not rely on conformal coating as ESD protection in my applications.

Henry said...

Conformal Coatings are essential to protect against moisture, dust, chemicals and extreme temperatures from electrical failure.

Mike Jhon said...

yes obviously conformal coating will help and prevent ESD.