Data Sheet
November 29, 2011
Thermal Considerations
ESTW010A0A Series Eighth-Brick Power Modules
36–75Vdc Input; 5.0Vdc Output; 10A Output Current
The power modules operate in a variety of thermal
environments; however, sufficient cooling should be
provided to help ensure reliable operation.
Considerations include ambient temperature, airflow,
module power dissipation, and the need for increased
reliability. A reduction in the operating temperature of
the module will result in an increase in reliability. The
thermal data presented here is based on physical
measurements taken in a wind tunnel.
The thermal reference points, T
ref1
and T
ref2
, used in
the specifications for open frame modules are shown
in Figure 13. For reliable operation these
o
o
temperatures should not exceed 110 C and 125 C
respectively.
OUTPUT CURRENT, I
O
(A)
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 15. Output Current Derating for the Open
Frame Module; Airflow in the Transverse Direction
from Vout(+) to Vout(-); Vin =48V.
OUTPUT CURRENT, I
O
(A)
AIRFLOW
Figure 13. T
ref 1 &
T
ref2
Temperature Measurement
Locations for Open Frame Module.
The thermal reference point, T
ref
, used in the
specifications for modules with heatplate is shown in
Figure 14. For reliable operation this temperature
o
should not exceed 110 C.
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 16. Output Current Derating for the Module
with Heatplate; Airflow in the Transverse Direction
from Vout(+) to Vout(-); Vin =48V.
Figure 14. T
ref
Temperature Measurement
Location for Module with Heatplate.
OUTPUT CURRENT, I
O
(A)
Heat Transfer via Convection
Increased airflow over the module enhances the heat
transfer via convection. Derating curves showing the
maximum output current that can be delivered by
each module versus local ambient temperature (T
A
)
for natural convection and up to 1m/s (200 ft./min)
forced airflow are shown in Figure 15.
Please refer to the Application Note “Thermal
Characterization Process For Open-Frame Board-
Mounted Power Modules” for a detailed discussion of
thermal aspects including maximum device
temperatures.
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 17. Output Current Derating for the Open
Frame Module with Heatplate and 0.25” Heatsink;
Airflow in the Transverse Direction from Vout(+) to
Vout(-); Vin =48V.
LINEAGE
POWER
9
LINEAGEPOWER [ LINEAGE POWER CORPORATION ]
