JFW100G Lineage Power, JFW100G Datasheet - Page 17

• Manufacturer Part Number: JFW100G
• Manufacturer: Lineage Power

April 2008
Thermal Considerations
Heat Transfer with Heat Sinks
Use Figure 25 to determine air velocity for the 1/2 inch
heat sink. The minimum airflow necessary for this mod-
ule is about 2.0 m/s (400 ft./min.).
Custom Heat Sinks
A more detailed model can be used to determine the
required thermal resistance of a heat sink to provide
necessary cooling. The total module resistance can be
separated into a resistance from case-to-sink (θcs) and
sink-to-ambient (θsa) shown below (Figure 26).
Figure 26. Resistance from Case-to-Sink and
Lineage Power
P
D
Sink-to-Ambient
∅
T
C
θcs
dc-dc Converters; 36 to 75 Vdc Input; 2.5 Vdc Output; 25 W to 75 W
T
S
(continued)
θsa
(continued)
T
A
8-1304 (C)
For a managed interface using thermal grease or foils,
a value of θcs = 0.1 °C/W to 0.3 °C/W is typical. The
solution for heat sink resistance is:
This equation assumes that all dissipated power must
be shed by the heat sink. Depending on the user-
defined application environment, a more accurate
model, including heat transfer from the sides and bot-
tom of the module, can be used. This equation pro-
vides a conservative estimate for such instances.
EMC Considerations
For assistance with designing for EMC compliance,
please refer to the FLTR100V10 data sheet
(DS99-294EPS).
Layout Considerations
Copper paths must not be routed beneath the power
module mounting inserts. For additional layout guide-
lines, refer to the FLTR100V10 data sheet
(DS99-294EPS).
θsa
=
(
----------------------- -
T
C
P
–
D
T
A
)
–
θcs
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