User Guide
40 of 46
Rev. 1.0
2022-03-09
48V Battery Switch Reference Design
R 48V BATT Switch10
System performance
4
System performance
4.1
Thermal performance
The power board is mounted on an aluminum heat sink for cooling. Due to the thermal prepreg layer between
the middle and the bottom layer there is no need for extra isolation between the board and the heat sink. Even
without adding thermal grease the performance is sufficient. With moderate air flow provided by a standard
12V PC fan running at low speed, located 20 cm away from the board, the maximum board temperature settles
at 80°C after 30 minutes at 25°C ambient temperature. Figure 46 shows the temperature distribution across the
board at the end of this test.
Figure 46
Temperature distribution after 30 min. at 300 A
Figure 47
Temperature rise (max. board temperature at 300 A vs. time)
20,00
30,00
40,00
50,00
60,00
70,00
80,00
90,00
0
2 0 0
4 0 0
6 0 0
8 0 0
1 0 0 0
1 2 0 0
1 4 0 0
1 6 0 0
1 8 0 0
T
m
a
x
[°
C
]
Time [s]
