h24sn12012nrfa Delta Electronics, Inc., h24sn12012nrfa Datasheet - Page 11

• Manufacturer Part Number: h24sn12012nrfa
• Description: Delphi Series H24sn, 350w Half Brick Family Dc/dc Power Modules 18~36vin, 28v/12.5a
• Manufacturer: Delta Electronics, Inc.

H24SN28012_07272006
THERMAL CONSIDERATIONS
Thermal management is an important part of the system
design. To ensure proper, reliable operation, sufficient
cooling of the power module is needed over the entire
temperature range of the module. Convection cooling is
usually the dominant mode of heat transfer.
Hence, the choice of equipment to characterize the
thermal performance of the power module is a wind
tunnel.
Thermal Testing Setup
Delta’s DC/DC power modules are characterized in
heated vertical wind tunnels that simulate the thermal
environments
equipment. This type of equipment commonly uses
vertically mounted circuit cards in cabinet racks in which
the power modules are mounted.
The
characterization setup. The power module is mounted
on a test PWB and is vertically positioned within the
wind tunnel. The space between the neighboring PWB
and the top of the power module is constantly kept at
6.35mm (0.25’’).
Figure 19: Wind Tunnel Test Setup
Note: Wind Tunnel Test Setup Figure Dimensions are in millimeters and (Inches)
MEASURED BELOW
TEMPERATURE
following
AIR VELOCITY
AND AMBIENT
THE MODULE
FACING PWB
encountered
figure
AIR FLOW
shows
PWB
in
50.8 (2.0”)
MODULE
12.7 (0.5”)
the
most
wind
electronics
tunnel
Thermal Derating
Heat can be removed by increasing airflow over the module.
The module’s maximum case temperature is
enhance system reliability, the power module should always
be operated below the maximum operating temperature. If
the
temperature, reliability of the unit may be affected.
THERMAL CURVES
Figure 20: Temperature measurement location
The allowed maximum hot spot temperature is defined at 115
Figure 21: Output power vs. hot spot temperature (Either
Orientation)
400
350
300
250
200
150
100
50
0
25
Output Power (W)
temperature
35
H24SN28012NR A (Standard) Output Power vs. Hot Spot Temperature
45
exceeds
55
(Either Orientation)
65
the
75
maximum
85
Hot Spot Temperature(℃)
95
115
℃
module
105
.
℃
To
11