Application Note AN-1039
IR2159: Dimming Dual Lamp Parallel Configuration
with Balance Transformer
By T. Ribarich, R. Marenche
1. Basic Circuit Considerations........................................................... 1
2. Figure 1: Dual Lamp Parallel Configuration.................................... 2
3. Schematic....................................................................................... 3
4. Bill of Materials ............................................................................... 4
The IR2159 dimming ballast control IC can be used with some modifications to the ballast output
stage, to allow both lamps to be dimmed while maintaining equal brightness in both lamps.
Through externally programmable components, the IR2159 offers flexibility of various features
such as preheat time and current and minimum and maximum brightness settings.
Comprehensive protection features protect the circuit against conditions such as lamp strike
failures, filament failures, low DC bus, thermal overload, or lamp failure during normal operation.
This circuit switches off both lamps when one is taken out, and automatically restarts when both
lamps are in place.
APPLICATION NOTE
AN1039
International Rectifier •233 Kansas Street El Segundo CA 90245 USA
IR2159: Dimming Dual Lamp Parallel
Configuration with Balance Transformer
By T. Ribarich, R. Marenche
TOPICS COVERED
Basic Circuit Considerations
Schematic Diagrams
Bill of Materials
A popular and economical configuration for dimmable fluorescent ballasts is for driving two lamps in
parallel. The IR2159 dimming ballast control IC can be used with some modifications to the ballast output
stage, to allow both lamps to be dimmed while maintaining equal brightness in both lamps. Through
externally programmable components, the IR2159 offers flexibility of various features such as preheat time
and current and minimum and maximum brightness settings. Comprehensive protection features protect the
circuit against conditions such as lamp strike failures, filament failures, low DC bus, thermal overload, or
lamp failure during normal operation. This circuit switches off both lamps when one is taken out, and
automatically restarts when both lamps are in place.
1. BASIC CIRCUIT CONSIDERATIONS
The output stage has been modified for two lamps in parallel (Figure 1). The lamps have been placed
outside the under-damped resonant circuit loop which consists of L3 and C15. The filament heating during
preheat and dimming is achieved using voltage-mode filament heating with secondary windings off of the
resonant inductor (L3A, L3B, L3C, L3D). A balance transformer (L4) provides equal currents through both
lamps such that equal brightness is obtained during dimming. The DC blocking capacitor, C16, is also
placed outside the under-damped resonant circuit loop such that it does not influence the natural resonance
frequency of L3 and C15. During lamp removal, both lower filament signals are OR-ed into the shutdown
pin, SD, through resistors R16 and R18.
1
AC Rectified Line
R20
L3
L4
(+)
C16
R11
L3A
L3B
(4T)
(4T)
RVDC
CVDC
C18
C17
R12
R13
1
VDC
HO
16
2
VCO
VS
15
3
CPH
VB
14
M2
C15
CVCO
C14
C9
5
MAX
6
7
D4
VCC
13
COM
12
MIN
LO
11
FMIN
CS
10
RMAX
R21
R22
C10
D5
C11
R14
CMIN
R19
DIM
IR2159
4
C13
M3
R17
CPH
R15
D6
L3C
L3D
(4T)
(4T)
R16
RFMIN
RMIN
8
IPH
SD
9
R18
RIPH
CCS
C12
C19
RCS
D7
(-)
Figure 1, Dual lamp parallel configuration.
2
C20
X1E
(-)
(+)
X1D
C1
RV1
C2
BR1
C3
R3
R2
R1
R6
C4
R5
R4
C5
R7
4
3
2
1
5
6
7
C6
C7
R9
R10
M1
C8
D2
CDIM
D3
CMIN
RMAX
CPH
CVCO
CVDC
RVDC
R11
RFMIN
MAX
MIN
FMIN
IPH
5
6
7
8
RIPH
DIM
CPH
VCO
VDC
4
3
2
1
14
VB
SD
CS
LO
CCS
9
10
11
COM 12
13
15
VS
VCC
16
HO
C10
D4
R21
C9
C12
R13
Note: Thick traces represent high-frequency, high-current paths. Lead
lengths should be minimized to avoid high-frequency noise problems
MC34262
8
D1
R8
IR2159
0.5 to 5VDC
DIM INPUT
GND
N
L
L1
RDIM
L2
RMIN
3
R15
R14
M3
RCS
R16
C11
R22
R12
R17
R18
M2
D5
C13
R19
D6
C14
D7
C15
L3
C19
(4T)
C20
(4T)
L3D
(4T)
L3C
L3B
C17
L3A
L4
C18
(4T)
C16
R20
Schematic
Bill Of Materials
Lamp type: T8/36W X 2
Line Input Voltage: 180..255 VAC/50..60 Hz
Note: Different lamp types require different frequency programming components.
Item #
1
Qt
1y
International Rectifier
DF10S
2
1
Roederstein
WY0222MCMBF0K
Capacitor, 2.2nF 275 VAC Y Cap
C1
3
1
Roederstein
F1772433-2200
Capacitor, 0.33uF 275 VAC
C2
4
1
Wima
MKP10
Capacitor, 0.1uF 400 VDC
C3
5
3
Panasonic
ECU-V1H103KBM
Capacitor, 0.01uF SMT 1206
C4, CVCO, CDIM
6
2
Panasonic
ECJ-3YB1E474K
Capacitor, 0.47uF SMT 1206
C5,C6
7
1
Panasonic
EEU-FC1H2R2
Capacitor, 2.2uF 50VDC 105C
C7
8
1
Panasonic
EEU-EB2V100
Capacitor, 10uF 350VDC 105C
C8
Manufacturer
Part Number
Description
Bridge Rectifier, 1A 1000V
Reference
BR1
9
4
Panasonic
ECU-V1H104KBM
Capacitor, 0.1uF SMT 1206
C9,C10,C12, CMIN
10
1
Panasonic
EEU-FC1H4R7
Capacitor, 4.7uF 50VDC 105C
C11
11
2
Vitramon
1812A102KXE
Capacitor, 1nF 1KV SMT 1812
C13,C14
12
1
Wima
MKP10
Capacitor, 6.8 nF,1600V
C15
13
1
Panasonic
ECQ-E4224KZ
Capacitor, 0.22uF, 400V
C16
14
4
Panasonic
ECU-S1H474KBB
Capacitor, 0.47uF, 50V
C17, C18, C19, C20
15
2
Panasonic
ECJ-3VB1E334
Capacitor, 0.33uF, SMT 1206
CVDC,CCPH
16
1
Panasonic
ECU-V1H471KBM
Capacitor, 470pF SMT 1206
CCS
17
4
Diodes
LL4148DICT-ND
Diode, 1N4148 SMT DL35
D1, D3, D5, D6
18
2
International Rectifier
10BF60
Diode, SMT SMB
D2, D4
19
1
Diodes
MMSZ4702T1
Diode, Zener 20V SMT DL35
D7
20
1
Motorola
MC34262
IC, Power Factor Controller
IC1
21
1
International Rectifier
IR2159
IC, Ballast Driver
IC2
22
1
Panasonic
ELF-15N007A
EMI Inductor, 1X10mH 0.7Apk
L1
23
1
RGA
RGA-EF25
PFC Inductor, 2.0mH 2.0Apk
L2
24
1
L3, L3A,L3B, L3C, L3D
25
1
Panasonic
ELF-15N008A
Inductor, 1.0mH, 2.0Apk with 4
secondary windings of 4 turns
EMI Inductor, 1X6.8mH 0.8Apk
26
3
International Rectifier
IRF840
Transistor, MOSFET
M1, M2, M3
27
2
Panasonic
ERJ-8GEYJ680K
Resistor, 680K ohm SMT 1206
R1, R2
28
1
Panasonic
ERJ-8GEYJ7.5K
Resistor, 7.5K ohm SMT 1206
R3
29
2
Panasonic
ERJ-8GEYJ820K
Resistor, 820K ohm SMT 1206
R4, R5
30
2
Panasonic
ERJ-8GEYJ10K
Resistor, 10K ohm SMT 1206
R6, RDIM
31
2
Panasonic
ERJ-8GEYJ100K
Resistor, 100K ohm SMT 1206
R7,R20
32
1
Panasonic
ERJ-8GEYJ22K
Resistor, 22K ohm SMT 1206
R8
33
3
Panasonic
ERJ-8GEYJ22
Resistor, 22 ohm SMT 1206
R9, R13, R14
34
1
Dale
CW-1/2
Resistor, 0.8 ohm ½ watt
R10
35
1
Yageo
1.0MQBK-ND
Resistor, 1.0megohm ¼ watt
R11
36
1
Yageo
470KQBK-ND
Resistor, 470Kohm ¼ watt
R12
37
1
Panasonic
ERJ-8GEYJ1K
Resistor, 1K ohm SMT 1206
R15
38
2
Yageo
330KQBK-ND
Resistor, 330K ohm ¼ watt
R16,R18
39
2
Yageo
1.0MQBK-ND
Resistor, 1.0M ohm ¼ watt
R17,R19
40
1
Dale
CW-1/2
Resistor, 0.75 ohm ½ watt
RCS
41
1
Panasonic
ERJ-8GEYJ19K
Resistor, 19K ohm SMT 1206
RMAX
42
1
Panasonic
ERJ-8ENF24.9K
Resistor, 24.9K ohm SMT 1206
RMIN
43
1
Panasonic
ERJ-8GEYJ30K
Resistor, 30K ohm SMT 1206
RFMIN
44
1
Panasonic
ERJ-8GEYJ12K
Resistor, 12K ohm SMT 1206
RIPH
45
1
Panasonic
ERZ-V05D471
Transient Suppressor
RV1
46
2
Panasonic
ERJ-8GEYJ10
Resistor, 10 ohm SMT 1206
R21, R22
Total
71
4
L4A, L4B