GE Industrial Solutions SHHN000A3 HAMMERHEAD Series - Manual (Page 8)

GE
Datasheet
SHHN000A3 Series; DC-DC Converter Power Modules
9Vdc – 36Vdc input; +15V, -15V Dual Output, 0.3A 9W Output
December 6, 2013
©2013 General Electric Corporation.
All rights reserved.
Page 8
Thermal Considerations
The power modules shall operate in a variety of thermal
environments.
The thermal data shall be gathered based on physical
measurements taken in a wind tunnel, using automated
thermo-couple instrumentation to monitor key component
temperatures: FETs, diodes, control ICs, magnetic cores,
ceramic capacitors, opto-isolators, and module pwb
conductors, while controlling the ambient airflow rate and
temperature. For a given airflow and ambient temperature, the
module output power is increased, until one (or more) of the
components reaches its maximum derated operating
temperature, as defined in IPC-9592A. This procedure is then
repeated for a different airflow or ambient temperature until a
family of module output derating curves is obtained.
Figure 12. Thermal Test Setup .
The thermal reference point, T
ref
used in the specifications shall
be defined based on actual data. For reliable operation this
temperature should not exceed 110°C
Figure 13. T
ref
Temperature Measurement Location.
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 are shown in Figures 14 - 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.
O
U
TP
UT CURR
ENT, I
O
(A
)
AMBIENT TEMEPERATURE, T
A
( o C )
Figure 14. Output Current Derating for the Open Frame
Module; Airflow in the Transverse Direction from V
out
(-) to
V
out
(+); V
IN
=18V, V
O
=+15V, -15V
Tref
0.0
0.1
0.2
0.3
0.4
20 30 40 50 60 70 80 90
NC