ICB2FL01G Datasheet, PDF (22/56 Pages) Infineon Technologies AG – Smart Ballast Control IC for Fluorescent Lamp Ballasts

2^nd Generation FL-Controller for FL-Ballasts
Functional Description
2.4.3 PFC Structure of Mixed Signal
A digital NOTCH filter eliminates the input voltage ripple - independent from the mains frequency. A
subsequent error amplifier with PI characteristic cares for a stable operation of the PFC pre converter
(Figure 16).
Over Voltage
109%
PFCVS
Σ∆-ADC
Open Loop
12.5%
Notch Filter
PI Loop Control
PWM
Gate Drive
PFCGD
Under Voltage
75%
Over Current
1V ± 5.0%
PFCCS
Bus Voltage
95%
ZCD Start Up
1.5V / 0.5V
THD
Correction
PFCZCD
Int. Reference
VPFCVS = 2.5 V
Clock 870 kHz
Figure 16: Structure of the mixed digital and analog control of the PFC pre converter
The zero current detection (ZCD) is sensed by the PFCZCD pin via R13 (Figure 3). The information of
finished current flow during demagnetization is required in CritCM and in DCM as well. The input is
equipped with a special filtering including a blanking of typically 500 ns and a large hysteresis of
typically 0.5 V and 1.5 V V_PFCZCD (Figure 16).
Datasheet
Page 22 of 56
ICB2FL01G
V1.2