ICB2FL02G Datasheet, PDF (17/55 Pages) Infineon Technologies AG – Smart Ballast Control IC for Fluorescent Lamp Ballasts

2^nd Generation FL-Controller for FL-Ballasts
Functional Description
2.3 Filament Detection during Start Up and Run Mode
The low and high side filament detection is sensed via the RES and the LVS pins. The low side
filament detection during start up and run mode is detected via the RES pin only. An open high side
filament during start up will be sensed via the LVS and the RES pins.
2.3.1 Start Up with broken Low Side Filament
A source current of I_RES3 = - 21.3 µA out of the RES pin (12) monitors during a start up (also in Run
mode) the existence of a low side filament. In case of an open low side filament during the start up
hysteresis (10.6V < V_CC < 14.1V) a capacitor (C19 in Figure 3) will be charged up via I_RES3 = - 21.3 µA.
When the voltage at the RES pin (12) exceeds V_RES1 = 1.6 V, the controller prevents a power up and
clamps the RES voltage internally at V_RES = 5.0 V. The gate drives of the PFC and inverter stage do
not start working.
V_CC
17.5 V
16.0 V
14.1 V
Start UP with open LOW Side Filament
Chip Supply Voltage
10.6 V
Start Up
VRES ^{UVLOHysteresis}
5.0 V
No Power UP
1.6 V
1.3 V
IRES
21.3µA
17.7µA
V_Lamp
Time
Time
Time
Time
Figure 8 Startup with open Low Side Filament _{Figure 9 Restart from open Low Side Filament}
The IC comparators are set now to a threshold of V_RES1 = 1.3V and to I_RES4 = - 17.7µA, the controller
waits until the voltage at the RES pin drops below V_RES1 = 1.3V.When a filament is present (Figure 9
section 2), the voltage drops below 1.3V and the value of the source current out of the RES pin is set
from I_RES4 = - 17.7 µA up to I_RES3 = - 21.3 µA. Now the controller powers up the system including Soft
Start and Preheating into the Run mode.
Preliminary Datasheet
Page 17 of 55
ICB2FL02G
V1.2