Additional information
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Revision 4.0
2021-10-11
Recommendations for board assembly of Infineon transistor outline
type packages
Mounting of surface-mount devices
Minimum reflow conditions
The lower temperatures and durations of an optimal reflow profile must stay above those of the solderability
qualification. The solderability of the terminations of Infineon components is tested according to the standards
IEC 60068-2-58 and J-STD-002 [2][4].
Maximum reflow conditions and cycles
Components that are moisture-sensitivity level (MSL) classified by Infineon have been tested by three reflow
runs in accordance with the J-STD-020 standard, including a double-sided reflow and one rework cycle. The
maximum temperatures must not be exceeded during board assembly. Please refer to the product barcode
label on the packing material that states this maximum reflow temperature according to the J-STD-020 [5]
standard as well as the MSL according to the J-STD-033 standard [6].
Typical Infineon TO SMD packages are generally suited for mounting on double-sided PCBs. Solder joints of
components on the first PCB side will reflow again in the second step. In the peak zone of the reflow profile (i.e.
where the solder is liquid), the components are only held in place by wetting forces from the molten solder.
Gravity acting in the opposite direction will elongate the solder joints, unlike joints on the top side, where
gravity will force the components closer to the PCB surface. This shape will be frozen during cooling and
therefore will result in a higher stand-off on the bottom side after the reflow process. Heavy vibrations in a
reflow oven may cause devices to drop off the PCB. That can be prevented by applying an appropriate SMD
adhesive prior to the reflow.
For further information about reflow soldering, please refer to
the General Recommendations for Board
Assembly of Infineon Packages
document that is available on the Infineon web page [1]. Please also feel free to
contact your local sales, application, or quality engineer.
3.5
Wave soldering of SMD
In general, Infineon TO SMD packages are not designed to withstand a wave soldering process in which the
whole package body will be immersed in the molten solder. The application of an appropriate SMD adhesive
prior to the soldering should be considered. In case wave soldering is applied to TO SMD, individual
investigations on a per-product basis are necessary.
For further information about wave soldering of TO SMD packages, please contact your local sales, application,
or quality engineer.
