60 DESIGN007 MAGAZINE I MARCH 2020
ure. Choosing the correct resin is not as easy
as it may seem, as there are so many variables
to consider, such as typical operating condi-
tions, expected extremes, the size and geome-
try of the units, the need for repair, the expect-
ed service life, etc. If the resin is too brittle,
it can crack during operation and expose the
electronics to potentially harmful chemicals. If
the unit is expected to undergo cyclic thermal
shock during its service life, then a flexible res-
in would be advised, but it depends on the
maximum and minimum temperature expect-
ed. There is a lot of difference between –60 to
+60°C and +40 to +160°C; both are a 120°C
temperature difference, but for one, a polyure-
thane resin would be recommended, while for
the other, epoxy would be better.
Conclusion
If ever in doubt, refer to the technical data
sheets (TDS); these can be a great help when
you embark on a new design or production
schedule with new components and resins.
However, if you do anticipate any glitches with
matching resin types to your production proce-
dures and find it hard to resolve this from the
TDS, please contact your supplier's technical
support team for further advice. Next time, I
will take an in-depth look at some of the most
frequently asked questions fielded by our Tech-
nical Support Team and explore options to fully
address these enquirie
s. DESIGN007
Alistair Little is the global
business technical director of
the resins division for Electrolube.
To read past columns from
Electrolube, click here. Download
your free copy of Electrolube's book,
The Printed Circuit Assembler's Guide to... Conformal
Coatings for Harsh Environments, and watch their
micro webinar series, "Coatings Uncoated".
Judy Warner gets the update on IPC Design, the newly launched program, from Teresa Rowe and Patrick
Crawford. They also discuss the impact on designers, the scope and cost of the program, how it will work,
and where you can get more information. Click image to view video.
IPC Design: The Newly Launched Program
