IR2156
(S) & (PbF)
State Diagram
Power Turned On
UVLO Mode
/
2
-Bridge Off
I
QCC
≅
120µA
CPH = 0V
CT = 0V (Oscillator Off)
CS > 1.3V
(Lamp Removal)
or
SD > 5.1V
or
VCC < 9.5V (UV-)
(Power Turned Off)
VCC < 9.5V
(VCC Fault or Power Down)
or
SD > 5.1V
(Lamp Fault or Lamp Removal)
1
VCC > 11.5V (UV+)
and
SD < 5.1V
FAULT Mode
Fault Latch Set
1
/
2
-Bridge Off
I
QCC
≅
180µA
CPH = 0V
VCC = 15.6V
CT = 0V (Oscillator Off)
1
PREHEAT Mode
/
2
-Bridge oscillating @ f
PH
RPH // RT
CPH Charging @ I
CPH
= 5
µA
CS Enabled @ CPH > 7.5V
R
VDC
to COM = 12.6kΩ @
CPH > 7.5V
CPH > 10V
(End of PREHEAT Mode)
CS > 1.3V
(Failure to Strike Lamp)
Ignition Ramp
Mode
RPH Open
f
PH
ramps to f
RUN
CPH charging
CPH > 13V
CS > 1.3V
(Lamp Fault)
RUN Mode
RPH = Open
1/2-Bridge Oscillating @
f
RUN
6
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