www.fairchildsemi.com
Fairchild Reference Design RD-552
The following reference design supports inclusion of FL7734MX in design of an LED
Driver with Phase-cut dimmable function. It should be used in conjunction with the
FL7734MX datasheet. Please visit Fairchild’s website at http://www.fairchildsemi.com.
Application
Fairchild
Device
Input Voltage
Range
Rated
Output
Power
Output Voltage
(Rated Current)
Topology
LED Driver
FL7734
108-132 VAC
56 W
46 V (1220 mA)
Flyback
Key Features
Performance








< ±1.8% Total Constant Current Tolerance Over All Conditions
< ±1.7% Over low Line Voltage Variation
< 0.2% from 45% to 100% Load Voltage Variation
Excellent Dimmer Compatibility by Active Dimming Control
Programmable Dimming Curve and Input Current Management
Fast Startup utilizing Bleeding Circuit
o < 0.1 s at the Max. Dimmer Phase Angle
o <0.5 s at the Min. Dimmer Phase Angle
Power Factor Correction in Non-dimming Mode
Constant LED Current Regulation in Large Phase Angle Range
System Protection







LED Short / Open Protection
Output Diode Short Protection, Sensing Resistor Short / Open Protection
VDD Over-Voltage Protection (OVP)
VDD Under-Voltage Lockout (UVLO)
Over-Temperature Protection (OTP)
All Protections are Auto Restart (AR)
Cycle-by-Cycle Current Limit
© 2015 Fairchild Semiconductor Corporation
1
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
1. Schematic
F1
R22
12k
C14
3.3n
R127
180k
ZD3
15V
MOV1
C111
68n
R20
33k
C19
2n
LF1
40mH
C13
470n
R23
91k
BD1
G3SBA60
C112
Open
R21
82k
C15
1u
Q4
2N7002K
R111
250
C114
330n
R28
620k
PG
VDD
R27
75k
VS
GATE
FL7734
MOD
BLD
BIAS
CS
TCIC
HOLD
DIM
FB
VIN
MBLD RBLD
SG
C18
100p
C8
22u/35V
R11
120
R10
47
R33
D3
1N4148WS 2k
ZD4
24V
R12
620k
R13
1k
C9
6.8n
D5
EGP30K
R17
15
Q3
FCPF600N60Z
Q1
FCPF600N60Z
R29
51
R115
200/2W
R114
200/2W
R116
2R0/2W
ZD2
R117 6.2V
1k
C6
8.2n
D1
1N4007
R118
36k
C116
150n
R119
91k
L1
1.0 m
C117
680n
R120
100k
C124
R121
100k
R122
100k
R16
51
C4
10n
D4
RS1M
R14 R15
0R22 0R27
R19
27k
R18
220k
D2
1N4007
R128
0R22
Q2
FCPF600N60Z
C10
10p
T1
PQ3220
R124
30
R125
30
C120
470u/63V
C119
560pF/500V
D6
RURP1560
C17
220pF
C121
470u/63V
C122
470u/63V
R30
200k
VLED+
VLED-
RD-552_FL7734 • Rev. 1.0
2
© 2015 Fairchild Semiconductor Corporation
Schematic
Figure 1.
www.fairchildsemi.com
2. Transformer
Required Components
PQ3220, 12P[V]
1
1
9
12
NP1
NS
2
MFG: TDK
Material: PC40
Core: PQ3220
Bobbin: 12-pin, remove pins 2,3,10
Insulation Tape: Polyester,
.050mm, 3M 1350 or Eq.
NP2
11
3
4
NA
6
7
5
Top View
Figure 2.
Transformer Bobbin Structure and Pin Configuration
NA(4 à5)
NP2(2 à1)
Start
NS (9 à11)
2mm Barrier
NP1(3 à2)
Figure 3.
Transformer Winding Structure
2.1. Winding Specification
Winding
Pins
(S→F)
Wire
(Diameter)
Turns
Layers
NP1
3→2
0.45 φ
7
1
Winding
Direction
Winding
Method
Forward
Solenoid
Insulation: 1 tape layer between coil and finish lead, 1 tape layer after winding
NS
9→11
0.7 φ TIW
16
1
Forward
Solenoid
Insulation: 1 tape layer between coil and finish lead, 1 tape layer after winding
NP2
2→1
0.45 φ
7
1
Forward
Solenoid
Insulation: 1 tape layer between coil and finish lead, 1 tape layer after winding
NA
4→5
0.2 φ
8
1
Forward
Solenoid
Insulation: 1 tape layer between coil and finish lead, 3 tape layers after winding
© 2015 Fairchild Semiconductor Corporation
3
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
2.2. Electrical Characteristics
Pin
Specification
Remarks
Inductance
3→1
100 µH ± 5 %
50 kHz, 1 VAC
Leakage
3→1
< 10 µH
Short all other pins
3. Bill of Material
Item
No.
Part
Reference
1
F1
2
MOV1
3
Part Number
Description
Manufacturer
SS-5-2A
2 A/250 V Fuse
SVC471D-10A
Metal Oxide Varistor
BD1
G3SBA60
4 A / 600 V, Bridge Diode
4
R111
MOR 1W TC 270
Metal Oxide Film Resistor RSD Type J 270 /1W R-Forming
ABC
5
R114
MOR 2W TC 200R
Metal Oxide Film Resistor RSD Type J 200  /2W R-Forming
ABC
6
R115
MOR 2W TC 200R
Metal Oxide Film Resistor RSD Type J 200  /2W R-Forming
ABC
7
R116
MOR 2W TC 2R
Metal Oxide Film Resistor RSD Type J 2  /2W R-Forming
8
R117
RC0805 JR-071KL
1 k SMD Resistor 2012 F 1/8W
Yageo
9
R118
RC0603 JR-0736KL
36 k SMD Resistor 1608 F 1/16W
Yageo
10
R119
RC0603 JR-0791KL
91 k SMD Resistor 1608 F 1/16W
Yageo
11
R120
RC1206JR-07100KL
100 k SMD Resistor 3216 F 1/4W
Yageo
12
R121
RC1206JR-07100KL
100 k SMD Resistor 3216 F 1/4W
Yageo
13
R122
RC1206JR-07100KL
100 k SMD Resistor 3216 F 1/4W
Yageo
14
R123
MOR 1W TC 3R3K
Metal Oxide Film Resistor RSD type J 3.3  / 1W R-Forming
15
R124
RC1206 JR-0730RL
30  SMD Resistor 3216 F 1/4W
Yageo
16
R125
RC1206 JR-0730RL
30  SMD Resistor 3216 F 1/4W
Yageo
17
R127
RC0603 JR-07180KL
180 k SMD Resistor 1608 F 1/16W
Yageo
18
R128
RC1206 JR-070R22RL
0.22  SMD Resistor 3216 F 1/4W
Yageo
19
R10
RC1206 JR-0747RL
47  SMD Resistor 3216 F 1/4W
Yageo
20
R11
RC1206 JR-07120RL
120  SMD Resistor 3216 F 1/4W
Yageo
21
R12
RC1206 JR-07620KL
620 k SMD Resistor 3216 F 1/4W
Yageo
22
R13
RC0805 JR-071KL
1 k SMD Resistor 2012 F 1/8W
Yageo
23
R14
RC1206 JR-070R22RL
0.22  SMD Resistor 3216 F 1/4W
Yageo
24
R15
RC1206 JR-070R27RL
0.27  SMD Resistor 3216 F 1/4W
Yageo
25
R16
RC0805 JR-0751RL
51  SMD Resistor 2012 F 1/4W
Yageo
26
R17
RC0805 JR-0715RL
15  SMD Resistor 2012 F 1/4W
Yageo
27
R18
RC0603 JR-07220KL
220 k SMD Resistor 1608 F 1/16W
Yageo
28
R19
RC0603 JR-0727KL
27 k SMD Resistor 1608 F 1/16W
Yageo
29
R20
RC0603 JR-0733KL
33 k SMD Resistor 1608 F 1/16W
Yageo
30
R21
RC0603 JR-0782KL
82 k SMD Resistor 1608 F 1/16W
Yageo
31
R22
RC0603 JR-0712KL
12 k SMD Resistor 1608 F 1/16W
Yageo
32
R23
RC0603 JR-0791KL
91 k SMD Resistor 1608 F 1/16W
Yageo
33
R27
RC0805 JR-0775KL
75 k SMD Resistor 2012 F 1/4W
Yageo
34
R28
RC1206 JR-07620KL
620 k SMD Resistor 3216 F 1/4W
Yageo
35
R29
RC0805 JR-0751RL
51  SMD Resistor 2012 F 1/4W
Yageo
36
R30
RC0805 JR-07200KL
200 k SMD Resistor 2012 F 1/8W
Yageo
37
R32
RC0805 JR-078R2L
8R2  SMD Resistor 2012 F 1/8W
Yageo
38
R33
RC0603 JR-072KL
2 k SMD Resistor 1608 F 1/16W
Yageo
© 2015 Fairchild Semiconductor Corporation
4
Bussmann
Samwha
Vishay
ABC
ABC
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
Bill of Material
(Continued)
Item
No.
Part
Reference
39
C111
MPE 400V683
MPE 68 nF/400 V 12.0 x 10.0 x 5.0 mm P 10 mm
40
C114
TF334*2*10B
MTF 330 nF/400 V 12.0 x 13.0 x 5.5 mm P 10 mm
Sungho
Electronics
CARLI
41
C116
TF154*2*10
MTF 150 nF / 400 V 12.5 x 9.5 x 5.0 mm P 10 mm
CARLI
42
C117
TF684*2*10
MTF 680 nF / 400 V 17.5 x 12.5 x 5.5 mm P 15 mm
CARLI
43
C119
C1206C561KCRACTU
560 pF / 500 V, SMD Capacitor 0805
Kemet
44
C120
KMG 470 μF / 63 V
470 μF / 63 V, Electrolytic Capacitor
Samyoung
45
C121
KMG 470 μF / 63 V
470 μF / 63 V, Electrolytic Capacitor
Samyoung
46
C122
KMG 470 μF / 63 V
470 μF / 63 V, Electrolytic Capacitor
Samyoung
47
C4
C1206C103KDRACTU
10 nF / 1 kV SMD Capacitor 3216
49
C6
GRM1885C1E822JA01#
8.2 nF / 16 V SMD Capacitor 1608 COG
50
C8
KMG 22μF35V
KMG Series 22 µF/35 V D5 x H11 105°C Electrolytic Capacitor
51
C9
GRM2192C1H682JA01#
6.8 nF/50 V SMD Capacitor 2012 CH
Murata
52
C10
C0603C100K8GACTU
10 pF/10 V SMD Capacitor 1608 NP0
Kemet
53
C13
GRM188B11A474KA61#
470 nF/10 V SMD Capacitor 1608 B
Murata
54
C14
GRM1881X1E332JA01#
3.3 nF/10 V SMD Capacitor 1608 SL
Murata
55
C15
GRM185D71A105KE36#
1 μF/10 V SMD Capacitor 1608 X7T
56
C17
GRM188B11A474KA61#
Y Cap 220 pF
57
C18
GRM1882C1H101JA01#
100 pF / 50 V SMD Capacitor CH
Murata
Samwha
capacitor
Murata
58
C19
GRM1881X1E202JA01#
2 nF / 10 V SMD Capacitor 1608 SL
Murata
59
LF1
B82733F
40 mH Common Inductor
EPCOS
Part Number
Description
Manufacturer
Kemet
Murata
Samyoung
60
L1
R06102KT00
Radial Inductor 1.0 mH Size Φ10 mm x H16 mm P 8 mm
61
T1
PQ3220 Core
PQ Core, 12-Pin Transformer
62
D1
1N4007
1000 V / 1.0 A DO-41 Package General Purpose Diode
Fairchild
63
D2
1N4007
1000 V / 1.0 A DO-41 Package General Purpose Diode
Fairchild
63
D3
1N4148WS
100 V / 0.3 A SOD-323 Package General Purpose Diode
Fairchild
64
D4
RS1M
1000 V / 1.0 A SMA Package Fast Recovery Diode
Fairchild
65
D5
EGP30K
800 V / 3.0 A DO-201AD Package
Fairchild
66
D56
RC0603 JR-070R0L
0  SMD Resistor 1608 F 1/16W
67
D6
RURP1560
600 V / 15 A, Ultrafast Rectifier
Fairchild
68
ZD4
1N4749
24 V Zener Diode DO-41
Fairchild
69
ZD2
MM3Z6V2B
6.2 V Zener Diode SOD-323
Fairchild
70
ZD3
MM3Z15VB
15 V Zener Diode SOD-323
Fairchild
71
Q3
FCPF600N60Z
N-Ch Mosfet 600 V / 7.4 A TO-220
Fairchild
72
Q3
FCPF600N60Z
N-Ch Mosfet 600 V / 7.4 A TO-220
Fairchild
73
Q3
FCPF600N60Z
N-Ch Mosfet 600 V/ 7.4 A TO-220
Fairchild
74
Q4
2N7002K
N-Ch Mosfet 60 V / 0.3 A SOT-23
Fairchild
75
U
FL7734MX
Phase Cut Dimmable LED Driver IC
Fairchild
© 2015 Fairchild Semiconductor Corporation
5
BOSUNG
TDK
Yageo
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
4. Performance
16
15
14
13
12
11
10
9
8
7
6
5
108Vac
Load CC
= ± 1.8%
120Vac
132Vac
0 100 200 300 400 500 600 700 800 900 1000110012001300140015001600
Figure 4.
Output Current Regulation Data Plotted against Output Voltage Change
Table 1. Output Current Regulation by Output Voltage Change (21-46 V)
Input Voltage
IOUT Minimum (mA)
IOUT Maximum (mA)
Tolerance (±%)
108 VAC [60 Hz]
1198
1238
1.64
120 VAC [60 Hz]
1199
1240
1.68
132 VAC [60 Hz]
1199
1241
1.72
© 2015 Fairchild Semiconductor Corporation
6
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
100
90
80
14 LED
7 LED
70
60
50
100
110
Figure 5.
120
130
140
System Efficiency Data Plotted against Line Variation
Table 2. System Efficiency 21-46 V Nominal Load
Input Voltage
Input
Power (W)
Output
Current (mA)
Output
Voltage (V)
Output Power
(W)
Efficiency
(%)
108 VAC [60 Hz]
65.7
1228
46
56.4
85.9
120 VAC [60 Hz]
64.9
1230
46
56.5
87.1
132 VAC [60 Hz]
64.2
1228
46
56.4
87.9
108 VAC [60 Hz]
64.3
1198
21
55.1
85.7
120 VAC [60 Hz]
63.9
1199
21
55.1
86.2
132 VAC [60 Hz]
63.7
1199
21
55.1
86.5
© 2015 Fairchild Semiconductor Corporation
7
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
PF
THD
1
19.00%
0.98
17.00%
0.96
15.00%
7 LED PF
0.94
13.00%
14 LED PF
11.00%
7 LED THD
0.92
9.00%
0.9
7.00%
0.88
5.00%
100
Figure 6.
14 LED THD
110
120
130
140
PF and THD Data Plotted against Line Variation – 140 V Nominal Load
Table 3. Power Factor and Input Current THD
Input Voltage
Output Current (mA)
Output Voltage (V)
Power Factor
THD (%)
108 VAC [60 Hz]
1228
46
0.99
12.00
120 VAC [60 Hz]
1230
46
0.98
11.00
132 VAC [60 Hz]
1228
46
0.99
10.60
108 VAC [60 Hz]
1198
21
0.98
11.00
120 VAC [60 Hz]
1199
21
0.97
11.50
132 VAC [60 Hz]
1199
21
0.96
11.90
© 2015 Fairchild Semiconductor Corporation
8
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
Output Current [mA]
Low-line FL7734 driver (56 W with 14 LEDs)
+10%
Output current without dimmer
1400
7 LED
1200
9 LED
1000
-25%
800
11 LED
600
13 LED
-70%
400
14 LED
200
0
0
10
20
30
40
50
60
70
80
90 100 110 120 130 140 150 160 170 180 Phase
Dimmer
Minimum
Dimmer
Maximum
Figure 7.
Angle
[degree]
Dimming Curve
Figure 7 shows a dimming curve which is obtained by rotating the dimmer switch.
Regardless of input line voltage ±10% variation, LED current is constantly regulated
from 180 to 130° dimmer phase angle .When the phase angle is below 130°, LED current
decreases linearly according to internal dimming reference modulation.
Figure 8.
NEMA SSL-7A Specification
FL7734 dimming control method can meet NEMA SSL-7A specification. Figure 8
indicates the maximum and minimum dimmed output range as specified by NEMA SSL7A.
© 2015 Fairchild Semiconductor Corporation
9
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
5. Electromagnetic Interference(EMI)
Figure 9.
Figure 10.
© 2015 Fairchild Semiconductor Corporation
10
Live
Neutral
RD-552_FL7734 • Rev. 1.0
www.fairchildsemi.com
6. Related Resources
FL7734- Product Folder
Reference Design Disclaimer
Fairchild Semiconductor Corporation (“Fairchild”) provides these reference design services as a benefit to our customers. Fairchild has made a good
faith attempt to build for the specifications provided or needed by the customer. Fairchild provides this product “as is” and without “recourse” and
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© 2015 Fairchild Semiconductor Corporation
11
RD-552_FL7734 • Rev. 1.0