JW100F Lineage Power, JW100F Datasheet - Page 13

• Manufacturer Part Number: JW100F
• Manufacturer: Lineage Power

April 2008
Thermal Considerations
Introduction
Note: Top view, pin locations are for reference only.
Figure 26. Case Temperature Measurement
The temperature at this location should not exceed
100 °C. The output power of the module should not
exceed the rated power for the module as listed in the
Ordering Information table.
Although the maximum case temperature of the power
modules is 100 °C, you can limit this temperature to a
lower value for extremely high reliability.
For additional information on these modules, refer to
the Thermal Management JC-, JFC-, JW-, and JFW-
Series 50 W to 150 W Board-Mounted Power Modules
Technical Note
(TN97-008EPS).
Heat Transfer Without Heat Sinks
Increasing airflow over the module enhances the heat
transfer via convection. Figure 31 shows the maximum
power that can be dissipated by the module without
exceeding the maximum case temperature versus local
ambient temperature (T
through 4 m/s (800 ft./min.).
Lineage Power
Measurements shown in millimeters and (inches).
7.6 (0.3)
Location
(continued)
V
ON/OFF
CASE
V
I
I
38.0 (1.50)
(+)
(–)
A
) for natural convection
dc-dc Converters; 36 to 75 Vdc Input, 3.3 Vdc Output; 33 W to 99 W
+ SEN
– SEN
V
V
TRIM
O
O
(–)
(continued)
(+)
MEASURE CASE
TEMPERATURE HERE
8-716 (C).f
Note that the natural convection condition was mea-
sured at 0.05 m/s to 0.1 m/s (10 ft./min. to 20 ft./min.);
however, systems in which these power modules may
be used typically generate natural convection airflow
rates of 0.3 m/s (60 ft./min.) due to other heat dissipat-
ing components in the system. The use of Figure 31 is
shown in the following example.
Example
What is the minimum airflow necessary for a JW100F
operating at V
maximum ambient temperature of 40 °C?
Solution
Given: V
Determine P
Determine airflow (v) (Use Figure 31.):
Figure 27. JW050F Power Dissipation vs.
9
8
7
6
5
4
3
2
I
T
P
v = 1.7 m/s (340 ft./min.)
0
O
A
I
D
= 54 V
= 20 A
= 40 °C
Output Current
= 15.8 W
1
D
I
(Use Figure 29.):
V
= 54 V, an output current of 20 A, and a
I
= 54 V
V
2
I
= 75 V
OUTPUT CURRENT, I
3
4
5
6
V
O
I
(A)
= 36 V
7
8
9
8-1459 (C)
10
13