© 2012 Fairchild Semiconductor Corporation
12
FEBFL7701_L31H008A • Rev.1.0.2
8.1.
Typical Waveforms: Startup
Figure 9 through Figure 12 show the typical startup performance at different input
voltage conditions. When AC input voltage is applied to the system, the FL7701
automatically operates in AC Mode after finishing an internally fixed, seven-cycle, soft-
start period. Figure 11 and Figure 12 show the soft-start characteristics when a DC input
voltage is applied.
CH1: V
CC
,
CH2: V
DRAIN
,
CH3: V
LED
,
CH4: I
LED
Figure 9. Soft-Start, AC Mode, 187 V
AC
CH1: V
CC
,
CH2: V
DRAIN
,
CH3: V
LED
,
CH4: I
LED
Figure 10. Soft-Start, AC Mode, 264 V
AC
CH1: V
CC
,
CH2: V
DRAIN
,
CH3: V
LED
,
CH4: I
LED
Figure 11. Soft-Start, DC Mode, 150 V
DC
CH1: V
CC
,
CH2: V
DRAIN
,
CH3: V
LED
,
CH4: I
LED
Figure 12. Soft-Start, DC Mode, 200 V
DC