IRF IRPLDIM1E Dimming ballast control ic design kit Datasheet

Not recommended for new designs - please refer to IRPLDIM3
IRPLDIM1E
International Rectifier • 233 Kansas Street, El Segundo, CA 90245 USA
IR21592 Dimming Ballast Control IC Design Kit
Features
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Drives:
1 x 36W T8 Lamp
Input:
185-265VAC/50Hz
High Power Factor/Low THD
High Frequency Operation
Lamp Filament Preheating
Lamp Fault Protection with Auto-Restart
Brownout Protection
IR21592 HVIC Ballast Controller
Description
The IRPLDIM1E is a high efficiency, high power factor, dimming electronic ballast designed for driving rapid start fluorescent lamp types. The design contains an EMI filter, active power factor correction and a ballast control circuit using the IR21592. This demo board is intended to ease the
evaluation of the IR21592 Dimming Ballast Control IC,
demonstrate PCB layout techniques and serve as an aid
in the development of production ballast’s using the IR21592.
IR21592
Dimming Ballast
Block Diagram
EMI Filter
Rectifier
PFC
Output Stage
Lamp
Line
IR21592
Interface
Dim
Input
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Half-Bridge Driver
Dimming Feedback
Preheat Feedback
Lamp Fault
1
Electrical Characteristics
Parameter
Units
Lamp Type
Input Power (100%)
Input Current (100%)
Filament Preheat Current
Preheat Mode Lamp Voltage
Preheat Time
Input AC Voltage Range
Input DC Voltage Range
Power Factor
Total Harmonic Distortion
Maximum Output Voltage
[W]
[Arms]
[Arms]
[Vrms]
[s]
[VACrms]
[VDC]
[%]
[Vpk]
Value (IRPLDIM1E)
36W T8
36
0.16
0.6
220
1.0
185..255/50..60Hz
250..350
0.98
<15
750
Note: Measurements performed with input AC line voltage = 230Vrms
Fault Protection Characteristics
Fault
Line voltage low
Upper filament broken
Lower filament broken
Failure to ignite
Open circuit (no lamp)
Ballast
Deactivates
Deactivates
Deactivates
Deactivates
Deactivates
Restart Operation
Increase line voltage
Lamp exchange
Lamp exchange
Lamp exchange
Lamp exchange
Fault Protection
Overview
The IRPLDIM1E Demo Board consists of an EMI filter, an active power factor correction front end, a
ballast control section and a resonant lamp output stage. The active power factor correction section
is a boost converter operating in critical conduction mode, free-running frequency mode. The ballast
control section provides frequency modulation control of a traditional RCL lamp resonant output
circuit and is easily adaptable to a wide variety of lamp types. The ballast control section also provides the necessary circuitry to perform closed-loop dimming, lamp fault detection, shutdown and
auto-restart. All functional descriptions refer to the IRPLDIM1E schematic diagram.
2
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(L)
X1A F1
X1B
L1
RV1
-
C1
BR1
+
R1
R2
R5
R4
C3
LPFC
D1
R6
IC1
8
3
C4
7
1
2
4
R7
R9
D2
RS
C5
MPFC
LINE INPUT
(N)
CY
C2
R3
R10
R11
R12
+
CBUS
RVDC
CVDC
CVCO
CPH
RDIM
CDIM
RFMIN
X1C
X1D
X1E
CMIN
RMIN
(E)
(+)
(-)
RMAX
5
L6561
6
1
2
3
4
5
6
7
8
VB
VS
HO
IR21592
VDC
VCO
CPH
VCC
COM
DIM
MAX
CS
LO
SD
MIN
IPH
FMIN
16
15
14
9
10
11
12
13
CVCC1
C10
ICBALLAST
RIPH
RLM2
C7
RLM1
D3
R13
+
CVCC2
R14
R15
R16
C11
D4
R17
RCS
MHS
MLS
C12
D5
RDC
CDC
LRES
CRES
X2A
X2B
X2C
X2D
3
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0.5 to 5VDC
DIM INPUT
IRPLDIM1E
Schematic Diagram
IRPLDIM1E Bill Of Materials
Lamp Type: T8/36W Line Input Voltage: 185 to 265 VAC/50/60Hz
1
2
3
4
5
6
7
8
Item
Qty
1
2
1
1
1
1
2
5
Reference
BR1
C4, CVDC
C5
C3
CVCO
C1
CDC,C2
C7,CVCC1,C11,CMIN,
CDIM
Description
Bridge Rectifier, 1A, 1000V
Capacitor, 0.47uF, SMT 1206
Capacitor, 1uF, SMT 1206
Capacitor, 0.01uF, SMT 1206
Capacitor, 0.022uF, SMT 1206
Capacitor, 0.33uF, 275VAC
Capacitor, 0.1uF, 400VDC
Capacitor, 0.1uF, SMT 1206
Manufacturer
International Rectifier
Panasonic
Panasonic
Panasonic
Panasonic
Roederstein
Wima
Panasonic
Part Number
DF10S
ECJ-3YB1E474K
ECJ-3YB1E105K
ECU-V1H103KBM
ECU-VIH223KBM
F1772433-2200
MKP10
ECJ-3VB1E104K
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
Total
1
1
1
1
1
1
2
2
1
1
1
1
1
1
3
1
1
2
2
2
2
1
1
1
1
2
1
1
2
2
1
1
1
1
1
1
1
1
1
2
66
CPH
CBUS
CVCC2
C10
C12
CRES
D1,D4
D2,D3
D5
IC1
IC2
L1
LPFC
LRES
MPFC,MHS,MLS
R15
RFMIN
RDIM, R12
RIPH,RMAX
RVDC,RMIN
R1,R2
R3
R4
R5
R6
R13,R14
R7
F1
R9,R16
R10,R11
R17
RS
RCS
RDC
X1
X2
J1
CY
RV1
RLM1,RLM2
Capacitor, 0.39uF, SMT 1206
Capacitor, 10uF, 450VDC,105C
Capacitor, 4.7uF, 25VDC,105C
Capacitor, 100pF, SMT 1206
Capacitor, 1nF,1KV, SMT 1812
Capacitor, 10nF, 1600VDC
Diode, 1N4148, SMT DL35
Diode, SMT SMB
Zener Diode, 20V, SMT DL35
IC, Power Factor Controller
IC, Dimming Ballast Controller
EMI Inductor, 1x10mH, 0.7A
PFC Inductor, 2.0mH, 2.0Apk
Inductor, 2.0mH, 2.0Apk
Transistor, MOSFET
Resistor, 1K Ohm, SMT 1206
Resistor, 33K Ohm, SMT 1206
Resistor, 10K Ohm, SMT 1206
Resistor, 24K Ohm, SMT 1206
Resistor, 27K Ohm, SMT 1206
Resistor, 680K Ohm, SMT 1206
Resistor, 7.5K Ohm, SMT 1206
Resistor, 470K Ohm
Resistor, 1M Ohm
Resistor, 22K Ohm, SMT 1206
Resistor, 22 Ohm, SMT 1206
Resistor, 100 Ohm, SMT 1206
Resistor, 0.5 Ohm, ½ Watt
Resistor, 100K Ohm, SMT 1206
Resistor, 820K Ohm, SMT 1206
Resistor, 1M Ohm, SMT 1206
Resistor, 1.2 Ohm, ¼ Watt
Resistor, 0.68 Ohm, ¼ Watt
Resistor, 100K Ohm, ¼ Watt
Connector, 5 terminal
Connector, 4 terminal
Jumper
Y-Capacitor
Varistor
Resistor, 10 Ohm, SMT 1206
Panasonic
Panasonic
Panasonic
Panasonic
Johanson
Panasonic
Diodes
International Rectifier
Diodes
ST
International Rectifier
Panasonic
Coilcraft
Coilcraft
International Rectifier
Panasonic
Panasonic
Panasonic
Panasonic
Panasonic
Panasonic
Panasonic
Yageo
Yageo
Panasonic
Panasonic
Panasonic
Dale
Panasonic
Panasonic
Panasonic
Yageo
Yageo
Yageo
Wago
Wago
ECJ-3YB1E394K
EEU-EB2W100
EEU-FC1H4R7
ECU-V1H101JCH
102S43W102KV4
ECW-H16103JV
LL4148
10DF60
ZMM5250B-7
L6561D
IR21592
ELF-15N007A
Z9264B
Z9265B
IRF820
ERJ-8GEYJ102V
ERJ-8GEYJ333V
ERJ-8GEYJ103V
ERJ-8GEYJ243V
ERJ-8GEYJ273V
ERJ-8GEYJ684KV
ERJ-8GEYJ752 V
CFR-25JR-470K
CFR-25JR-1M0
ERJ-8GEYJ223V
ERJ-8GEYJ220V
ERJ-8GEYJ101V
CW-1/2
ERJ-8GEYJ104V
ERJ-8GEYJ824V
ERJ-8GEYJ105V
CFR-25JR-1R2
CFR-25JR-R68
CFR-25JR-100K
Roederstein
Panasonic
Panasonic
WYO222MCMBFOK
ERZ-VO5D471
ERJ-8GEYJ100V
4
236-404
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Power Factor Correction
The power factor correction section consists of the L6561D Power Factor Controller IC (IC1), MOSFET
M1, inductor L2, diode D2, capacitor C8 and additional biasing, sensing and compensation components (see schematic diagram). This is a boost topology designed to step-up and regulate the output
DC bus voltage while drawing sinusoidal current from the line (low THD) which is “in phase” with the
AC input line voltage (HPF). The design of the power factor correction section was taken from the
L6561D data sheet and information on the operation and design considerations for the L6561D are
contained therein.
Ballast Control
The ballast control section is built around the IR21592 Ballast Control IC, IC2 of the Demo board.
The IR21592 contains an oscillator, a high voltage half-bridge gate driver, an analog dimming interface and lamp fault protection circuitry. A block diagram of the IR21592 IC is shown in figure 1 and a
state diagram of the IR21592 is shown in figure 2.
VCC
60uA
ICT
RFB
VCO 2
V
15uA
1uA
LEVEL
SHIFT
VDC 1
S
Q
R
Q
PULSE
FILTER &
LATCH
14
VB
16
HO
15
VS
13
VCC
11
LO
12
COM
10
CS
9
SD
ERR
1.3uA
CT
CPH 3
REF
5.1V
10V
ICT
DIM 4
S
5.1V
R
1.0V
S
Q
R1
T
Q
R
Q
R2 Q
15.6V
I DT +
Q
I CT
400ns
DELAY
CT
Q
IDIM
FB
MAX 5
4/RFMIN
MIN 6
0.1/R FMIN
0.1/R FMIN
IDIM/5
IFMIN
FMIN 7
5.1V
IPH
IGN
DET
8
3V
1/RFMIN
1.6V
1
5.1V
S
Q
R
Q
Q
S
Q
R
OVERTEMP
DETECT
UNDERVOLTAGE
DETECT
2.0V
7.6V
0
Figure 1: IR21592 Block Diagram
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5
Power Turned On
UVLO Mode
1/2-Bridge Off
IQCC=200mA
CPH=0V
Oscillator Off
VCC > 12.5V
and
VDC > 5.1V
and
SD < 1.7V
and
TJ < 165C
SD > 2.0V
(Lamp Removal)
or
VCC < 10.9V
(Power Turned Off)
T > 165C
J
(Over-Temperature)
FAULT Mode
Fault Latch Set
1/2-Bridge Off
IQCC=240µA
CPH=0V
VCC=15.6V
Oscillator Off
(UV+)
(Bus OK)
(Lamp OK)
(T jmax)
VCC < 10.9V
(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)
PREHEAT Mode
1/2-BridgeOscillator On
VCSPK+VIPH (Peak Current Control)
CPH Charging@I PH+1µA
DIM+Open Circuit
Over-Current Disabled
CPH > 5.1V
CS > V CSTH (1.6V)
(End of PREHEAT Mode)
(Failure to Strike Lamp
or Hard Switching)
or
T J > 165C
(Over-Temperature)
IGNITION Mode
fPH ramps to fMIN
CPH Charging@I PH+1µA
DIM=Open Circuit
Over-Current Enabled
CS > V
(1.6V)
CSTH
(Over-Current or Hard Switching)
or
TJ > 165C
VCS>VIPH(enable ignition detection)
(Over-Temperature)
then
VCS<VIPH(ignition detected)
DIM Mode
Phase CS=PhaseREF
DIM=CPH
Over-Current Enabled
Figure 2: IR21592 State Diagram
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The resulting operating frequency during preheat is given as:
Ballast Design
Lamp Requirements
Before selecting component values for the ballast output stage and the programmable inputs
of the IR21592, the following lamp requirements
must first be defined:
Variable
I ph
t ph
Description
Filament pre-heat current
Units
Arms
Filament pre-heat time
Vpp
Vign
Lamp ignition voltage
Vpp
P100%
Lamp power at 100% brightness
W
V100%
Lamp voltage at 100% brightness
Vpp
P1%
Lamp power at 1% brightness
W
V1%
Lamp voltage at 1% brightness
Vpp
Minimum cathode heating current
Arms
I Cathmin
2 I ph
[Hz]
πCV ph
f ign =
1
2π
4
π
1+
V DC
V ign
[Hz]
LC
(4)
The total load current during ignition is given
as:
I ign = f ign CVign 2π
[App] (5)
The operating frequency [Hz] at maximum lamp
power is given as:
f100%
Table I, Typical lamp requirements
Ballast Output Stage
The components comprising the output stage
are selected using a set of equations. Different
ballast operating frequencies and their respective voltages and currents are calculated. The
inductor and capacitor values are obtained using equations (2) through (7). The results of
these equations reveal the location of each
operating frequency and the corresponding voltages and currents. For a given L, C, DC bus
voltage, and pre-heat current, the resulting voltage over the lamp during pre-heat is given as:
1
=
2π
2
2
 1
32 P100
32 P 2 % 
1
%
−
+ 
− 2 100
 −4
4
4
LC C 2V100
%
 LC C V100% 
I Cath 1% =
V1 % f1%π C
2
(2)



2
(6)
(7)
Design Constraints
The inductor and capacitor values should be iterated until the following design constraints have
been fulfilled (Table II).
Design Constraint
f ph − f ign > 5kHz
2
 4VDC
1 − 
 V100%π
L2C 2
The cathode heating current at minimum lamp
power is given as:
V ph < V phmax
 V  8L 2 VDC
Vph =  DC  + I ph
−
[Vpp]
π
C
 π 
(3)
The resulting operating frequency during ignition is given as:
s
Maximum lamp pre-heat voltage
V phmax
f ph =
I ign < I ignmax
ICath1% ≥ ICathmin
Reason
Ignition during pre-heat
Production tolerances
Inductor saturation
Lamp extinguishing during
dimming
Table II, Ballast design constraints
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7
IR2159 Programmable Inputs
In order to program the MIN and MAX settings
of the dimming interface, the phase of the output stage current at minimum and maximum
lamp power must be calculated. This is obtained
using the following equations:
2
 4V 
1− DC 
2
2 2
1 1 32P%  1 32P% 
 V%π 
f% =
− 2 4 +  − 2 4  −4
2π LC C V% LC C V% 
L2C2
(8)
This ballast design procedure has been summarized into the following 3 steps:
Define
Lamp
Requirements
Calculate IR2159
Programmable
Inputs
Iterate L and C
to fulfill
constraints
Figure 3, Simplified Ballast Design Procedure
ϕ% =
2
%
2
%
180 −1 V
2P
V
tan [( C − 2% L)2πf% −4 LC2π3 f%3]
2P%
V%
P%
π
(9)
With the lamp requirements defined, the L and
C of the ballast output stage selected, and the
minimum and maximum phase calculated, the
component values for setting the programmable
inputs of the IR21592 are obtained with the following equations:
RFMIN =
(25e − 6) − ( f MIN − 10000) ⋅ (1e − 10)
( f MIN − 10000) ⋅ (2e − 14)
RCS =
8
[Ohms] (11)
[Ohms] (12)
CCPH = ( 2 E − 7)(t PH )
[Farads] (13)
R FMIN  ϕ 1% 
1 −

4 
45 
Included with the design kit is the Ballast Designer
Software which allows for selection of different
lamp types, different input voltage ranges or different lamp configurations. The software then
performes all of the necessary design iterations
and generates new schematics and a bill of materials.
[Ohms] (10)
RIPH = RFMIN RCS I ph 2
R MIN =
RMAX =
2⋅ (1.6)
I ign
Ballast Designer Software
[Ohms] (14)
0.86 ⋅ RFMIN ⋅ RMIN
[Ohms] (15)
 ϕ100% 
4 ⋅ RMIN − RFMIN ⋅ 1 −

45 

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IRPLDIM1E Design
L
C
[mH]
[nF]
V ph
[Vpp]
f ph
[kHz]
1) Lamp Requirements
f ign
[kHz]
Typical high-frequency (25kHz) lamp requirements for the 36W/T8 lamp type are given as:
I ign
[App]
f pmax
[kHz]
Line Input Voltage: 185 to 265VAC/50/60Hz
DC Bus Voltage: 400VDC
Lamp Power/Type: 36W/T8
Variable
2.0
6.8
700
2.0
8.2
622
2.0
10
546
57
53
49
51
46
42
1.4
1.6
1.8
42
42
41
0.32
0.35
0.38
Value
0.6
Units
Arms
t ph
1.0
s
Table IV, Ballast parameters for different C values.
V phmax
600
Vpp
Vign
1500
Vpp
Pmax
32
W
VPmax
282
Vpp
Pmin
1
W
VPmin
330
Vpp
I Cathmin
0.35
Arms
When compared against the lamp requirements,
a capacitor value of 6.8nF gives a lamp voltage
during pre-heat that exceeds the maximum allowable specified for this lamp type. This can
ignite the lamp before the cathodes have
reached their emission temperature, drastically
reducing lamp life. The pre-heat current can be
reduced to give a lower pre-heat voltage, but
the pre-heat time must then be increased for
proper heating. Also, I Cathmin is too low, which
will cause the lamp to extinguish at low light levels where the arc current alone is too low to heat
the cathodes. Increasing the capacitor value to
10nF fulfills the lamp requirements quite well,
even allowing some room in the pre-heat voltage for the pre-heat current to be increased and
the pre-heat time shortened. During dimming,
however, the lamp voltage increases with decreasing lamp power due to lamp negative incremental impedance effects. A maximum is
reached around 10% brightness, after which the
lamp voltage decreases as the lamp is further
dimmed. The maximum filament current occurs
at the maximum lamp voltage, which for a capacitor value of 10nF, is too high and will overheat the filaments. A capacitor value of 8.2nF
was chosen which fulfills the lamp requirements
without over-heating the cathodes.
I ph
Table III, 36W/T8 lamp requirements
2) Iterate L and C to Fulfill Constraints
To select the ballast output stage inductor and
capacitor, a range of values were inserted into
equations (2) through (7), which have been summarized in the following table:
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I Cath P
min
[Arms]
9
3) IR21592 Programmable Inputs
With all of the lamp requirements fulfilled, the component values for setting the programmable inputs
of the IR21592 are calculated as:
Equation No.
(8)
Variable
(8)
f1%
58kHz
(9)
ϕ100%
-56.12deg
(9)
ϕ 1%
-89.27deg
(10)
RFMIN
33kOhm
(11)
RCS
0.8 Ohm
(12)
RIPH
CTPH
RMIN
24kOhm
RMAX
24kOhm
(13)
(14)
(15)
f100%
Value
46kHz
330nF
27kOhm
Table V, IR21592 Programmable Inputs for T8/36W lamp.
Important Note: These design kits are intended as a demonstration of the functionality and performance of the IR21592 Dimming Ballast Control IC only. Adequate EMI filtering, line transient protection, galvanic dim control input isolation, and ballast and lamp life testing are not considered in this
design.
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Waveforms
Figure 4 shows the voltage appearing across the lamp while Figure 5 shows the current flowing
through the lamp during Startup, Preheat, Ignition and Dim modes.
Figure 4, Lamp voltage during Startup, Preheat,
Ignition and Dim (100%)
Figure 5, Lamp current during Startup, Preheat,
Ignition and Dim (100%) (100mA/div.)
Normal Powerdown
A Normal Powerdown occurs when the AC line voltage is disconnected from the ballast. When this
occurs the voltage on the VDC pin of IC2 drops below the line fault threshold (3V) and IC2 shuts
down in a controlled fashion. The oscillator is stopped, the half-bridge driver outputs (LO and HO)
are turned off and capacitor CPH is discharged. IC2 also goes into its UVLO/micro-power mode and
the bus voltage begins to collapse.
Fault Mode
Fault mode is when the ballast driver is shutdown due to the detection of a lamp fault. Note that when
the ballast is in this Fault mode the power factor correction section of the ballast is also shutdown
and the bus voltage will drop to the non-boosted/unregulated level. There are several lamp fault
conditions which can put the ballast into the Fault mode. The lamp fault conditions detected include:
near/below resonance (under-current) detection, hard-switching detection and over-current detection. Resistor RCS in the source lead of the low side MOSFET (M3) serves as the current sensing
point for the half-bridge which is used to detect these lamp fault conditions. In operation when the
half-bridge is oscillating, a voltage appears across RCS whenever the low side MOSFET, M3, is
turned on or the high side MOSFET, M2, is turned off. The magnitude of this voltage directly relates
to the current in the lamp resonant circuit. Figure 6 shows the voltage which appears across resistor
RCS during normal Run mode conditions while Figure 14 shows the voltage appearing across the
lamp during the end of Preheat mode, Ignition Ramp mode and the beginning of Run mode. Also
shown in Figure 7 are the gate drive signals for the low side MOSFET (LO pin) and the high side
MOSFET (HO-VS pin).
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11
Figure 6, Normal Run mode, Upper trace: voltage
across RCS, Middle trace: IC2 LO pin voltage,
Lower trace: IC2 HO-VS pin voltage
Figure 7, Normal lamp ignition: Lamp voltage during the
end of Preheat mode, Ignition Ramp mode and the
beginning of the Run mode
During the Preheat mode the over-current protection is disabled. However, at the end of Preheat
mode (the beginning of the Ignition mode) the hard-switching and over-current detection are enabled. If at any time thereafter the voltage magnitude across resistor RCS rises above the overcurrent threshold (1.6V) of the CS pin of IC2, a lamp fault condition is signaled and the half-bridge
output MOSFETs’, (M2 and M3) are turned off and the ballast goes into Fault mode. This can happen
if the lamp fails to ignite or if the upper filament is open. For failure to ignite the lamp, the current in
the half-bridge increases and thus the voltage across resistor RCS increases above the over-current
threshold signaling a fault. Figure 8 shows the voltage across resistor RCS and the voltage appearing across the lamp when the ballast detects a failure to ignite the lamp and goes into Fault mode.
Figure 9 shows the voltage appearing across the lamp during the tail end of the Preheat mode and
the Ignition mode for a failure of the lamp to ignite condition. If the upper filament is open, the halfbridge output hard-switches and each time the low side MOSFET (M3) is turned on a large current
pulse occurs and thus a large voltage pulse occurs across resistor RCS signaling a fault, Figure 10
shows this hard-switching condition. Figure 11 shows the lamp voltage during the Preheat mode and
beginning of Ignition Ramp mode for this hard-switching condition when the lamp fault condition is
detected. The ballast will remain in Fault mode until either the line voltage is cycled or a lamp replacement is performed.
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Figure 8, Failure of lamp to ignite condition (lamp
filaments good): Upper trace: voltage across
RCS, Lower trace: lamp voltage
Figure 9, Failure of lamp to ignite condition (lamp
filaments good): Lamp voltage during the end
of Preheat and Ignition Ramp modes
Figure 10, Hard-switching condition (upper trace
filament open): Upper trace: voltage across RCS,
Middle trace: IC2 LO pin voltage,
Lower trace: IC2 HO-VS pin voltage
Figure 11, Hard-switching condition (upper filament open):
Lamp voltage during Preheat mode and beginning of
Ignition Ramp mode when lamp fault is detected
IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245 Tel: (310) 252-7105
Data and specifications subject to change without notice. 8/8/2008
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REVISION HISTORY FOR REFERENCE DESIGN IRPLDIM1E
Date
Change
August 8, 2008
Added “Not recommended for new designs – please refer to IRPLDIM3
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