Datasheet

LTM4601/LTM4601-1
16
4601fd
For more information www.linear.com/LTM4601
Figure 7. 1.5V Power Loss Figure 8. 3.3V Power Loss
Figure 9. No Heat Sink 5V
IN
Figure 10. BGA Heat Sink 5V
IN
applicaTions inForMaTion
Thermal Considerations and Output Current Derating
The power loss curves in Figures 7 and 8 can be used
in coordination with the load current derating curves in
Figures 9 to 14 for calculating an approximate θ
JA
for the
module with various heat sinking methods. Thermal models
are derived from several temperature measurements at
the bench and thermal modeling analysis. Thermal Ap
-
plication Note 103 provides a detailed explanation of the
analysis for the thermal
models and the derating curves.
Tables 3 and 4 provide a summary of the equivalent θ
JA
for the noted conditions. These equivalent θ
JA
parameters
are correlated to the measured values, and are improved
with air flow. The case temperature is maintained at 100°C
or below for the derating curves. The maximum case
temperature of 100°C is to allow for a rise of about 13°C
to 25°C inside the µModule with a thermal resistance θ
JC
from junction to case between 6°C/W to 9°C/W. This will
maintain the maximum junction temperature inside the
µModule regulator below 125°C.
Safety Considerations
The LTM4601 modules do not provide isolation from
V
IN
to V
OUT
. There is no internal fuse. If required, a
slow blow fuse with a rating twice the maximum input
current needs to be provided to protect each unit from
catastrophic failure.
LOAD CURRENT (A)
0
0
POWER LOSS (W)
1.0
2.0
3.0
2
4
6 8
4601 F07
10
4.0
5.0
0.5
1.5
2.5
3.5
4.5
12
5V
IN
20V
IN
12V
IN
LOAD CURRENT (A)
0
0
POWER LOSS (W)
1
2
3
4
6
2
4 6 8
4601 F08
10 12
5
20V
IN
12V
IN
AMBIENT TEMPERATURE (°C)
50
0
MAXIMUM LOAD CURRENT (A)
2
4
6
8
10
12
60 70 80 90
4600 F09
100
5V
IN
, 1.5V
OUT
0LFM
5V
IN
, 1.5V
OUT
200LFM
5V
IN
, 1.5V
OUT
400LFM
AMBIENT TEMPERATURE (°C)
50
0
MAXIMUM LOAD CURRENT (A)
2
4
6
8
10
12
60 70 80 90
4601 F10
100
5V
IN
, 1.5V
OUT
0LFM
5V
IN
, 1.5V
OUT
200LFM
5V
IN
, 1.5V
OUT
400LFM