HDC2010: HDC2010 and conformal coating

Donald - 

if you mean that you will tape off HDC2010 section, conformal coat the board, then place the HDC2010, then use a filter over the HDC2010; that sounds reasonable. 

Hi Josh,

Thank you for your speedy reply. 

My plan has been to cover the HDC2010 with the Sensirion SF2 filter which would create a barrier between the conformal coating and the HDC2010.  I must admit mostly ignorance about conformal coatings.  After doing some reading about conformal coatings I'm wondering, considering  the HDC2010 humidity sensor's sensitivity to chemicals and the Parylene coating's appearing to be chemically inert if the Parylene could be a better match for the for a board using the HDC2010. 

These sensors will be a couple of hundred feet from the ocean; most are inside but a few outside.  Protecting the circuit board and the humidity sensor while exposing the humidity sensor to the air is challenging.  I believe the SF2 will protect the HDC2010.  If not then your suggestion will certainly be a consideration. 

I'm wondering if the chemical vapors in the parylene will be less damaging to the humidity sensor than the vapors in the other chemicals.

I am taking advantage of the ability to calibrate the humidity sensor during production after the board is built and wirelessly if needed post installation periodically.

Any information you can share will be greatly appreciated.

Thanks,

Donald Pierman

A friend of mine use to fly a Supper Constellation weather plane in the Navy.

Donald - 

The conformal coating is basically glue which will harden into a protective shell. You don't want to overcoat the sensor or the cover of the sensor with it - you still need to allow for sensor access to air (which contains the moisture being measured)

PS - did your buddy fly the EC-121 variant? cool

correct - was haze gray and underway for a while making sure those things kept an eye out for everyone :)