LTM4612
20
4612fc
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
