Rev. P05

16

VPN12AD02-FU

.

FIG.34 Analog Dimming

Soft Start Setting:

The soft start ramp is defined by a capacitor placed at the Soft_Start pin. Selection of the

capacitor can be done according to the following approximate formula. Vss_th_eff is the soft

start effectiveness threshold that depends on load condition. Its value is about 0.7 V for the

buck mode and 1.4 V for the boost mode

26uA

.