STEVAL-ILL013V1 Datasheet, PDF (22/43 Pages) STMicroelectronics – 80 W offline LED driver with PFC

UM0670
Measurement
Figure 18. Output LED current for different LED voltage (I_LED = 1000 mA)
VLED v s. ILED for nominal LED current 1 A
1200
1000
LED 800
current
[mA] ₆₀₀
400
200
0
63
84
103
122
LED voltage [V]
1A
AM00405
9.2
Power MOSFET turn ON and OFF time
The power MOSFET turn ON and OFF time is shown in Figure 19. Turn ON time is
approximately 50 ns and turn OFF time is approximately 120 ns (OFF time is used in
Equation 13 in the appendix).
Figure 19. Power MOSFET turn ON and OFF measurement
9.3
LED current ripple reduction
The output LED current ripple can be reduced by increasing the output capacitor size. For
example, inductor current ripple is 400 mA for the 100 nF / 450 V output capacitor, as shown
in Figure 20. Thanks to the larger 470 nF capacitor used on the STEVAL-ILL013V1, the
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