ICB1FL02G Datasheet, PDF (14/37 Pages) Infineon Technologies AG – Smart Ballast Control IC for Fluorescent Lamp Ballasts

ICB1FL02G
Functional Description
3.4 Detection of End-of-Life and Rectifier Effect
After ignition the lamp voltage breaks down to its run voltage level (typically 50Vpeak to 300Vpeak). Reaching the
run frequency there follows a time period of 250ms called Pre-Run Mode, in which some of the monitoring features
(EOL1, EOL2, Cap.Load1) are still disabled. In the subsequent Run Mode the End-of-life (EOL) monitoring is
enabled. The event EOL1 is detected by measuring the positive and negative peak level of the lamp voltage by a
current fed into the LVS pin (R17, R18,R19 in Fig. 11). If the sensed current exceeds 215µA for longer than 610µs
the status end-of-life (EOL1) or the exceeding of the maximum output power is detected. In Fig. 12 the different
levels of the sensed lamp voltage are illustrated.
VBUS
PFCZCD
PFCGD
PFCVS
C2
PFCCS
R17 R18 R19
R10
HSGD
HSVCC
C4
HSGND
R15 R16
Q2
L2
C5
C10
LSGD
LSCS
R11
D6
Q3
D7 C6 C8
R20
D9
Vcc
R30 ^R14
D8
R5 R12 R13 C7
Figure 11 Circuit diagram of the lamp inverter section.
C9
D10
+ Shut down level
+ Ignition level
V_LAMP-IGN
+ EOL Threshold
IV_L+PEAKI/IV _L-PEAKI
0
t
V_LAMP-RUN
- EOL Threshold
- Ignition level
- Shut down level
Figure 12 Sensed lamp voltage levels.
Datasheet Version 1.2
14
February 2006