User Manual
9 of 17
Rev.1.12
2020-04-02
TLD5542-1 Multichannel evalboard V4.5
User Manual
6
Operating range and power derating
Software power derating is implemented on SW 3.8, and it reduces output current (and thus the output power)
when the battery voltage drops below 9V at the board connector. Power derating profile is set as shown in
Figure 9 (6W/V).
P
out
[W]
6
9
18 V
bat
[V]
P
out-peak
P
out-average
40
25
50
32
Figure 9
Average (blue) and peak (red) output power derating profile
The SW V3.8 is limits only the peak output power (red curve on Figure 9), but if POS function is ON, then the
effective LB/HB average power available on LB is reduced to Pout-average (blue curve on Figure 9).
Please note that the module does not implement thermal protection, so ensure proper cooling when output
power is above 30 W. Place a heat sink below switching MOSFETs as shown on Figure 10.
Figure 10
TLD5542-1 Heat sink placement
The Heat sink should be thermally coupled but electrically insulated from the PCB by mean of a thermal pad.