JAW075B1 Lineage Power, JAW075B1 Datasheet - Page 13

• Manufacturer Part Number: JAW075B1
• Manufacturer: Lineage Power

April 2008
Thermal Considerations
Heat Transfer with Heat Sinks
Then solve the following equation:
Use Figure 22 to determine air velocity for the 1/4 inch
heat sink.
The minimum airflow necessary for this module is
0.86 m/s (170 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) as shown in Figure 23.
Figure 23. Resistance from Case-to-Sink and
Lineage Power
θ
θ
θ
ca
ca
ca
P
=
=
=
D
Sink-to-Ambient
3.8 °C/W
(
----------------------- -
(
----------------------- -
T
82 40
T
C
P
11
C
–
–
D
T
A
)
)
θ
cs
T
S
(continued)
θ
sa
(continued)
T
A
36 Vdc to 75 Vdc Input, 12 Vdc Output; 50 W to 75 W
8-1304 (F).e
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,
refer to the FLTR100V10 Filter Module Data Sheet
(DS99-294EPS).
Layout Considerations
Copper paths must not be routed beneath the power
module standoffs. For additional layout guidelines,
refer to the FLTR100V10 Filter Module Data Sheet
(DS99-294EPS).
θ
sa
=
(
------------------------ -
T
C
P
–
D
T
A
)
–
θ
cs
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