GE Industrial Solutions Austin Lynx II 12 V SMT - Manual (Page 15)

Data Sheet
October 1, 2009 Austin Lynx TM II 12 V SMT Non-Isolated Power Modules:
8.3 – 14.0 Vdc Input; 0.75Vdc to 5.5Vdc Output; 10A output current
LINEAGE POWER 15
Thermal Considerations
Power modules operate in a variety of thermal
environments; however sufficient cooling should always
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 test set-up is shown in Figure
33. Note that the airflow is parallel to the short axis of the
module as shown in figure 32. The derating data applies
to airflow in either direction of the module’s short axis.
Air Flow
T
ref
Top View
Figure 32. Tref Temperature measurement location.
The thermal reference point, T
ref
used in the
specifications is shown in Figure 32. For reliable
operation this temperature should not exceed 115
o C.
The output power of the module should not exceed the
rated power of the module (Vo,set x Io,max).
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.
Figure 33. Thermal Test Set-up.
Heat Transfer via Convection
Increased airflow over the module enhances the heat
transfer via convection. Thermal derating curves showing
the maximum output current that can be delivered at
different local ambient temperatures (T
A
) for airflow
conditions ranging from natural convection and up to
2m/s (400 ft./min) are shown in the Characteristics
Curves section.
Air
flow
x
Power Module
Wind Tunnel
PWBs
8.3_
(0.325)
76.2_
(3.0)
Probe Location
for measuring
airflow and
ambient
temperature
25.4_
(1.0)