Ehhd024a0a series: dc-dc converter power module, Datasheet, 18 to 75v – GE Industrial Solutions EHHD024A0A HAMMERHEAD Series User Manual
Page 10: Input; 5v, Thermal considerations (continued), Heat transfer via conduction

GE
Datasheet
EHHD024A0A Series: DC-DC Converter Power Module
18 to 75V
dc
Input; 5V
dc
, 24A, 120W Output
February 28, 2014
©2014 General Electric Corporation. All rights reserved.
Page 10
Thermal Considerations (continued)
OUT
PUT
CURR
ENT,
I
O
(A
)
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 17. Output Current Derating for the Module with
-18H Heatplate; Airflow in the Transverse Direction from
V
out
(-) to V
out
(+);V
IN
=48V, V
O
=5V
OUT
PUT
CURRENT
, I
O
(A
)
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 18. Output Current Derating for the Open Frame
Module; Airflow in the Transverse Direction from V
out
(-) to
V
out
(+); V
IN
=24V, V
O
=5V.
OUTPUT C
U
RR
EN
T, I
O
(A)
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 19. Output Current Derating for the Module with
Heatplate; Airflow in the Transverse Direction from V
out
(-)
to V
out
(+);V
IN
=24V, V
O
=5V.
OUTPUT C
U
RR
EN
T, I
O
(A)
AMBIENT TEMEPERATURE, T
A
(
o
C
)
Figure 20. Output Current Derating for the Module with
-18 Heatplate; Airflow in the Transverse Direction from
V
out
(-) to V
out
(+);V
IN
=24V, V
O
=5V.
Heat Transfer via Conduction
The module can also be used in a sealed environment with
cooling via conduction from the
module’s top surface through a gap pad material to a
cold wall, as shown in Figure 22. This capability is achieved
by insuring the top side component skyline profile achieves
no more than 1mm height difference between the tallest
and the shortest power train part that benefits from contact
with the gap pad material. The output current derating
versus cold wall temperature, when using a gap pad such as
Bergquist GP2500S20, is shown in Figure 21.
Figure 21. Cold Wall Mounting
OU
TP
U
T CURR
ENT,
I
O
(A
)
COLDPLATE TEMEPERATURE, T
C
(
o
C)
Figure 22. Derated Output Current versus Cold Wall
Temperature with local ambient temperature around
module at 85C; V
IN
=24V or 48V.
0
4
8
12
16
20
24
25
35
45
55
65
75
85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s)
400LFM
(2.0m/s)
0
4
8
12
16
20
24
25
35
45
55
65
75
85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s)
400LFM
(2.0m/s)
0
4
8
12
16
20
24
25
35
45
55
65
75
85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s)
400LFM
(2.0m/s)
0
4
8
12
16
20
24
25
35
45
55
65
75
85
NC
100LFM
(0.5m/s)
200LFM
(1.0m/s)
400LFM
(2.0m/s)
0
4
8
12
16
20
24
20
30
40
50
60
70
80
90