IR21571STRPBF Datasheet, PDF (7/18 Pages) International Rectifier – FULLY INTEGRATED BALLAST CONTROL IC

IR21571 State Diagram
IR21571(S) & (PbF)
Power Turned On
SD > 2.0V
(Lamp Removal)
or
VCC < 9.5V
(Power Turned Off)
UVLO Mode
1_{/2-Bridge Off}
I_QCC ≅ 150µA
CPH = 0V
Oscillator Off
VCC > 11.4V(UV+)
and
VDC > 5.1V(Bus OK)
and
SD < 1.7V(Lamp OK)
and
T_J < 160C (T_jmax)
FAULT Mode
Fault Latch Set
1_{/2-Bridge Off}
I_QCC ≅ 150µA
CPH = 0V
VCC = 15.6V
Oscillator Off
T_J > 160C
PREHEAT Mode
(Over-Temperature)
1_{/2-Bridge @PfH}
CPH Charging @_PI_H = 1µA
RPH = 0V
RUN = Open Circuit
CS Disabled
CS > CS+ Threshold
(Failure to Strike Lamp
or Hard Switching)
or
T_J > 160C
(Over-Temperature)
CPH > 4.0V
(End of PREHEAT Mode)
IGNITION RAMP Mode
f_PH ramps to_Mf_IN
CPH Charging @_PI_H = 1µA
RPH = Open Circuit
RUN = Open Circuit
CS+ Threshold Enabled
VCC < 9.5V
(VCC Fault or Power Down)
or
VDC < 3.0V
(dc Bus/ac Line Fault or Power Down)
or
SD > 2.0V
(Lamp Fault or Lamp Removal)
CS > CS+ Threshold
(Over-Current or Hard Switching)
or
CS < 0.2V
(No-Load or Below Resonance)
or
T_J > 160C
(Over-Temperature)
CPH > 5.1V
(End of IGNITION RAMP)
RUN Mode
f_MIN Ramps to_Rf_UN
CPH Charges to 7.6V Clamp
RPH = Open Circuit
RUN = 0V
CS- Threshold Enabled
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