Additional information
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Revision 4.0
2021-10-11
Recommendations for board assembly of Infineon transistor outline
type packages
Mounting of through-hole devices
and deflectors for the PCB or/and by creating a small wave shape in the machine by using special wave-guiding
tubes or covers.
4.5
Alternative mounting methods
Further techniques beside the previously described wave and reflow soldering methods might be used in
special applications. Examples include selective soldering, laser welding and laser soldering, hot bar soldering
and manual soldering with a soldering iron and hot air guns.
Some general guidelines should be followed for a wide variety of soldering techniques that cannot be tested for
every component:
The maximum temperature of the package body and leads must not exceed the maximum allowed
temperature for reflow or wave soldering.
The maximum allowed time at high temperatures must not exceed the maximum allowed time for reflow or
wave soldering.
If heat is applied to the leads, the maximum temperatures in the package and of the package body must not
exceed the maximum allowed temperatures during reflow or wave soldering.
If extended contact and heating times are unavoidable, the resulting temperature on various leads near the
package body should be measured and must not exceed the temperature and duration experienced during
wave or reflow soldering.
Pin-in-paste
Another technique used to solder THDs is to print solder paste onto a PCB near or over drill holes through
which the leads are then inserted. The reflow of the solder paste is done together with soldering the surface
mount components and therefore they have to go through the reflow temperature profile. Consequently, the
temperature is nearly the same for the whole package in contrast to wave soldering, and the time for which the
peak temperature is applied to the package is much longer compared to wave soldering.
Heat sink mounting by reflow soldering
In special applications the heat sink of high-power THD can be mounted to the board by solder paste printing,
pick-and-place, and reflow soldering. In this case, the product undergoes a reflow profile cylcle.
Note:
TO THD are qualified for wave soldering and not for reflow soldering. Therefore it is not
recommended to use reflow soldering for heat sink mounting of TO THD.
For further information about alternative mounting techniques, please refer to the individual product
Application Note
documents and contact your local sales, application, or quality engineer.
