
5
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 encountered in most electronics
equipment. This type of equipment commonly uses
vertically mounted circuit cards in cabinet racks in
which the power modules are mounted.
The following figure shows the wind tunnel
characterization setup. The power module is mounted
on a test PWB and is vertically positioned within the
wind tunnel. The space between the
facing PWB and
PWB is constantly kept at 25.4mm (1’’).
Figure 7:
Wind tunnel test setup
Thermal Derating
Heat can be removed by increasing airflow over the
module. To enhance system reliability, the power
module should always be operated below the maximum
operating temperature. If the temperature exceeds the
maximum module temperature, reliability of the unit
may be affected.
THERMAL CURVES
DS2E00series Output Current vs. Ambient Temperature and Air Velocity
(Either Orientation)
Output Power (%)
0%
20%
40%
60%
80%
100%
120%
25
35
45
55
65
85
A75
℃
)
Natural
Convection
Figure 8:
Derating Curve