Data Sheet
ESTW015A0F Series Eighth-Brick Power Modules
36–75Vdc Input; 3.3Vdc Output; 15A Output
August 20, 2010
Thermal Considerations
The power modules operate in a variety of thermal
environments; however, sufficient cooling should be
provided to help ensure reliable operation.
Please refer to the Application Note “Thermal
Characterization Process For Open-Frame Board-
Mounted Power Modules” for a detailed discussion of
the thermal aspects including maximum device
temperatures.
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, Trefx used in the
specifications for open frame modules are shown in
Figure 13. For reliable operation Tref1 and Tref2
temperatures should not exceed 125oC and Tref3
temperature should not exceed 110 oC.
Figure 13. Tref Temperature Measurement
Location for Open Frame Module.
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
the module versus local ambient temperature (TA)
for natural convection and up to 1m/s (200 ft./min)
forced airflow, are shown in Figure 14. Full power up
to TA=85 oC, is achieved for airflow of 1 m/s(200 LFM)
or greater.
16
15
NC
14
0.5m/s
(100LFM)
13
1.0m/s
(200LFM)
12
11
10
20
30
40
50
60
70
80
90
AMBIENT TEMEPERATURE, TA (oC)
Figure 14. Output Current Derating for the Open
Frame Module; Airflow in the Transverse Direction
from Vout(+) to Vout(-); Vin =48V.
LINEAGE POWER
9
LINEAGEPOWER [ LINEAGE POWER CORPORATION ]
