GE Industrial Solutions Austin MicroLynx II 12V SIP - Manual (Page 15)

Data Sheet
January 18, 2010
Austin MicroLynx II TM 12V SIP Non-isolated Power Modules:
8.3 – 14Vdc input; 0.75Vdc to 5.5Vdc Output; 6A output current
Thermal Considerations Thermal Considerations
Power modules operate in a variety of thermal
environments; however, sufficient cooling should be
provided to help ensure reliable operation. 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 test set-
up is shown in Figure 33. Note that the airflow is
parallel to the long axis of the module as shown in
Figure 32. The derating data applies to airflow in
either direction of the module’s long axis. 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 long axis of the module as shown in
Figure 32. The derating data applies to airflow in
either direction of the module’s long axis.
Air Flow
T
ref2
Top View
Bottom View
T
ref1 (inductor winding)
Figure 32. Tref Temperature measurement
location.
The thermal reference point, T
ref 1
used in the
specifications of thermal derating curves is shown in
Figure 32. For reliable operation this temperature
should not exceed 125
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.
Air
flow
x
Power Module
Wind Tunnel
PWBs
7.24_
(0.285)
76.2_
(3.0)
Probe Location
for measuring
airflow and
ambient
temperature
25.4_
(1.0)
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 by various module versus local
ambient temperature (T
A
) for natural convection and
up to 1m/s (200 ft./min) are shown in the
Characteristics Curves section.
LINEAGE POWER 15