Datasheet

© 2012 Fairchild Semiconductor Corporation 20 FEBFL7701_L30U003A • Rev. 1.0.2
9.4. Thermal Performance
Figure 30 through Figure 37 show the steady-state thermal results with different input
voltage conditions. Inductor L3 has the highest temperature on the top side of the PCB
due to copper resistance. The FL7701 has the highest temperature on the bottom side of
the PCB due to power loss associated with the high-voltage device. The IC temperature is
66.5°C for the 220V
AC
input condition.
Figure 30. Thermal Test Result, Bottom-Side
Temperature at 90V
AC
Condition (IC)
Figure 31. Thermal Test Result, Top-Side Temperature
at 90V
AC
Condition (Inductor)
Figure 32. Thermal Test Result, Bottom-Side
Temperature at 110V
AC
Condition (IC)
Figure 33. Thermal Test Result, Top-Side Temperature
at 110V
AC
Condition (Inductor)