LTM4608
20
4608fd
applicaTions inForMaTion
Safety Considerations
The LTM4608 modules do not provide isolation from V
IN
to V
OUT
. There is no internal fuse. If required, a slow blow
fuse with a rating twice the maximum input current needs
to be provided to protect each unit from catastrophic failure.
Layout Checklist/Example
The high integration of LTM4608 makes the PCB board
layout very simple and easy. However, to optimize its
electrical and thermal performance, some layout consid-
erations are still necessary.
• Use large PCB copper areas for high current path,
including V
IN
, GND and V
OUT
. It helps to minimize the
PCB conduction loss and thermal stress.
Figure 17. Recommended PCB Layout
For easier board layout and PCB assembly due to increased
spacing between land grid pads, please refer to the LTM4608A.
• Placehighfrequencyceramicinputandoutputcapaci-
tors next to the V
IN
, GND and V
OUT
pins to minimize
high frequency noise.
• Placeadedicatedpowergroundlayerunderneaththe
unit.
• Tominimizetheviaconductionlossandreducemodule
thermal stress, use multiple vias for interconnection
between top layer and other power layers.
• Donotputviasdirectlyonthepads,unlesstheyare
capped.
• UseaseparatedSGNDgroundcopperareaforcom-
ponents connected to signal pins. Connect the SGND
to GND underneath the unit.
Figure 17 gives a good example of the recommended layout.
GND
GND
GND
4608 F17
C
IN
C
OUT
C
OUT
C
OUT
C
IN
V
IN
V
OUT
