AN-1501
Application Note
www.power.com/igbt-driver
Page 4
Manual Soldering
Name
Leaded
Lead-Free
Solder iron temperature
320°C
340°C (SAC305)
Maximum solder time
3-4s
It is recommended to use lead-free solder EF2210, SAC305 alloy. However, other solder types may also be
used.
Mechanical Handling
The correct handling of mechanical gate drivers is based on two fundamental principles:
1)
No excessive mechanical force must be applied to transformers.
2)
No excessive mechanical force causing bending (reflected to IPC-T-650) must be applied to PCBs.
The root causes of possible driver failure mentioned above may appear during mounting and later during
operation. If the carrier PCB on which the driver core is placed is large, there is a risk of driver PCB bending
referred to the carrier PCB. These phenomena can be seen during vibrations tests where momentary
displacement between driver core and carrier PCB can be observed. Therefore if significant vibrations are
foreseeable, it is necessary to mechanically stabilize the driver.
Insertion of Gate Driver Cores into the Carrier PCB
It is recommended that no large steady-state or temporary mechanical force be applied to the transformers or
terminals of the gate core drivers. Applying excessive mechanical force to the transformer bends the PCB and
considerably stresses the transformer solder joints, leading to potential pre-damage. This increases the
probability of cracks at the transformer solder points and other assembled SMD components, especially
ceramic capacitors and resistors.
The transformer may be held by hand during removal or insertion from/into the packaging or assembly to
carrier PCB, but the PCB should be free from bending.
Fig. 1 illustrates the correct removal and assembly of the driver core. If mechanical force applied to
transformer causes PCB bending or excessive mechanical stress to the solder joints, the force must be shifted
directly to the corresponding terminals of the driver PCB.
Fig. 1 Not recommended (left) and recommended (right) ways of handling Power Integrations gate driver
cores during assembly (body plan of a driver)
Transformer
Transformer
