Datasheet

LTM4612
20
4612fb
applicaTions inForMaTion
Safety Considerations
The LTM4612 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 LTM4612 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,in-
cluding V
IN
, PGND and V
OUT
. It helps to minimize the
PCB conduction loss and thermal stress.
• Placehighfrequencyceramicinputandoutputcapaci-
tors next to the V
D
, PGND and V
OUT
pins to minimize
high frequency noise.
• Placeadedicatedpowergroundlayerunderneaththe
unit.
• UseroundcornersforthePCBcopperlayertominimize
the radiated noise.
• TominimizetheEMInoiseandreducemodulethermal
stress, use multiple vias for interconnection between
top layer and other power layers.
• Donotputviasdirectlyonpads.
• Ifviasareplacedontothepads,thetheviasmustbe
capped.
• Interstitialviaplacementcanalsobeusedifnecessary.
• UseaseparatedSGNDgroundcopperareaforcom-
ponents connected to signal pins. Connect the SGND
to PGND underneath the unit.
• Placeoneormorehighfrequencyceramiccapacitors
close to the connection into the system board.
Figure 17 gives a good example of the recommended
layout.
Figure 17. Recommended PCB Layout
SIGNAL
GND
V
OUT
V
IN
GND
C
OUT
C
IN
C
IN
C
OUT
4612 F17