FW300B1 Lineage Power, FW300B1 Datasheet - Page 15

• Manufacturer Part Number: FW300B1
• Description: CONVERTER DC/DC 12V 300W OUT
• Manufacturer: Lineage Power
• Series: FW300r
• Type: Isolated with Remote On/Offr

Specifications of FW300B1

• Output: 12V
• Number Of Outputs: 1
• Power (watts): 300W
• Mounting Type: Through Hole
• Voltage - Input: 36 ~ 75V
• Package / Case: Module
• 1st Output: 12 VDC @ 25A
• Size / Dimension: 4.60" L x 2.40" W x 0.53" H (116.8mm x 61mm x 13.5mm)
• Power (watts) - Rated: 300W
• Operating Temperature: -40°C ~ 100°C
• Efficiency: 87%
• Approvals: CE, CSA, UL, VDE
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• 3rd Output: -
• 2nd Output: -
• 4th Output: -

Data Sheet
March 2000
Thermal Considerations
Heat Transfer with Heat Sinks
Figure 24. FW300B1 Power Dissipation vs. Output
Example
If an 85 °C case temperature is desired, what is the
minimum airflow necessary? Assume the FW300B1
module is operating at V
of 25 A, maximum ambient air temperature of 40 °C,
and the heat sink is 1 inch.
Solution
Given: V
Determine P
Then solve the following equation:
Lucent Technologies Inc.
50
45
40
35
30
25
20
15
10
ca
ca
ca
5
0
0
I
T
T
Heat sink = 1 inch
P
O
=
=
=
A
C
I
D
= 25 A
= 54 V
= 40 °C
2
= 85 °C
= 45 W
1.0
Current at 25 °C
D
----------------------- -
----------------------- -
T
85 40
by using Figure 23:
4
C
°C/W
P
45
–
–
D
6
T
V
V
V
A
OUTPUT CURRENT, I
I
I
I
= 75 V
= 54 V
= 36 V
8
I
10
= 54 V and an output current
12
14 16 18
(continued)
O
FW250B1 and FW300B1 Power Modules: dc-dc Converters:
(continued)
(A)
20
36 Vdc to 75 Vdc Input, 12 Vdc Output; 250 W to 300 W
22
8-1733 (C)
24
Use Figures 21 and 22 to determine air velocity for the
1 inch heat sink. The minimum airflow necessary for
the FW300B1 module depends on heat sink fin orienta-
tion and is shown below:
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 ( cs) and
sink-to-ambient ( sa) as shown in Figure 25.
Figure 25. Resistance from Case-to-Sink and Sink-
For a managed interface using thermal grease or foils,
a value of cs = 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 provides
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).
1.4 m/s (270 ft./min.) (oriented along width)
1.7 m/s (330 ft./min.) (oriented along length)
sa
P
=
D
------------------------ -
to-Ambient
T
C
P
T
–
D
C
T
A
–
cs
cs
T
S
sa
T
A
8-1304(C)
15