Using LV5012MD in 120VAC, 14W Flyback for TRIAC dimming

LV5012MD-A19-120VEVM04
[ For A19/E27 LED Bulb Application ]
The single stage flyback converter for phase cut dimming
with High Power Factor
Application Note
Ver1.04
LV5012MD-A19-120VEVM04
Application Note
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1. Introduction
2. Features
3. Performance Specifications
3.1. Application constitution
3.2. Electrical characteristics
4. Schematic
5. Evaluation Board
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6. Test Setup
7. Test Procedure
7.1 Line/Load Regulation and Efficiency Measurement Procedure
7.2 Equipment Shutdown




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7.3 Phase Angle Decode vs LED Current (at dimming)
8. Performance Data
8.1 Efficiency
8.2 Power factor
8.3 Line regulation

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8.4 Output voltage/current operation waveform (No dimming)
8.5 Input voltage/current operation waveform (No dimming)
8.6 Switching operation waveform
8.7 LED current vs Phase angle
8.8 Dimming operation waveform
8.9 EMI data
9. Board Layout
10. Bill of materials
11. Transformer specification

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

12. Detailed Descriptions for Application Circuit Setting
12.1 Transformer design
12.2 REF_IN pin and ALC_C pin setting
12.3 CS pin setting
12.4 ACS pin and DML pin setting
12.5 HV pin setting
12.6 Protection function
1. Introduction
The LV5012MD-A19-120VEVM04 is a 14W, 120VAC isolated dimmable LED driver for A19 and
E27 applications. The LV5012MD-A19-120VEVM04 is a primary-side power regulated PFC
controller used for commercial and residential phase-cut dimmer compatible LED lamp drivers.
2. Features
• Primary Side Flyback Control With Integrated PFC
• Compatible With Leading and Trailing Edge Dimmer
• Constant Current & Improved THD
• Short Protection - [latch off]
• Over Voltage Protection -[auto recovery]
• 2 Stage Thermal Protection -[auto recovery]
3. Performance Specifications
3.1.
Application constitution
Isolation Flyback with Phase Cut Dimming
3.2.
Electrical characteristics (Operating Temperature = 25C)
Table1. LV5012MD-A19-120VEVM04 Electrical Performance Specifications
Description
Min
Typ
Max
Units
Input AC voltage
108
120
132
VAC
Output voltage
20
V
Output current
550
mA
Efficiency
83
%
Power Factor
0.96
Comment
2parallel of 6LEDs series
VAC=120V, 60Hz
VAC=120V, 60Hz
4. Schematic
AC1
R1
F1
10/1W
15/2W
C1
AC INPUT
AC2
R3
1k/1W
0.033uF
/AC275V
VR1
R2
L1
15/2W
0
D1
S1ZB60
L2
R4
0
C4
0.1uF
/630V
1.0mH
C5
2.2nF
/630V
C3
0.33uF/450V
C2
0.1uF
/630V
D4
MURA140
F
R5
R7
390k
270k
R9
1.0k
R10
12k
C12
4.7uF
/50V
U1
MMSD103
1
HV
OUT
DML
GND
2
Transformer T1 specifications
Inductance value
1-3 inductance Lp = 0.7mH
S-F inductance Ls = 32uH
Turns ratio
(4-6) : (S-F) = 1 : 1.14
3
4
NC
VIN
GND
CS
ENB
REF_IN
ACS
TRC
5
4
3.3k
R8
10k
R11
0
7
[Output=20V,550mA]
22
Q1
NDD03N50
R12
12
11
LED-
R16
R17
100k
4.7Meg
C11
2.2nF/AC250V
9
REF_OUT
ALC_C
R20
27k
S
10
6
R6
C10
1000uF
/35V
6
0
13
LED+
3
R15
14
D5
MBRS4201
2
LV5012MD
150pF
T1
1
D3
C7
(6 LEDs in series)×2parallel
[LED: NICHIA
NS6W083AT]
R14
100k
/1W
8
C8
C9
0.1uF
1uF
Figure1. LV5012MD-A19-120VEVM04 Schematic
R18
1.2
R19
0.91
5. Evaluation Board
LEDAC
INPUT
LED+
Figure2. LV5012MD-A19-120VEVM04 Transformer Side
64mm
24mm
Figure3. LV5012MD-A19-120VEVM04 IC Side
6. Test Setup
6.1 Test Equipment
Voltage Source: 120VAC AC source, NF EPO2000S
Power Meter: HIOKI 3332
Volt Meter: ADVANTEST R6441D DIGITAL MULTIMETER
AMP Meter: Agilent DIGITAL MULTIMETER 34401A
Output Load: 2 Parallel of 6 LEDs series (LED: NICHIA NS6W083AT)
Oscilloscope: LeCroy WaveRunner 6050A
Operating Temperature: 25C
6.2 Recommended Test Setup
Volt Meter
+
Power Meter
Neutral
AC Source
AC
INPUT
AMP
Meter
LED+
LV5012MD-A19-120VEVM04
Line
Dimmer
Min
Max
At No Dimming,
Connect this line
LED2 Parallel of 6 LEDs series
Figure4. LV5012MD-A19-120VEVM04 Recommended Test Set Up
6.3 List of Test Points
Table2. Test Points Functions
TEST POINTS NAME
DESCRIPTION
Neutral
120VAC neutral connection
Line
120VAC line voltage
LED+
LED anode connection
LED-
LED cathode connection
7. Test Procedure
7.1 Line/Load Regulation and Efficiency Measurement Procedure
1. Connect LV5012MD-A19-120VEVM like upper Figure4. An external LED load must be used
to start up the EVM.
2. Prior to turning on the AC source, set the voltage to 120VAC.
3. Turn on the AC Source.
4. Record the output voltage readings from Volt Meter and the output current reading from
AMP Meter. And Record the input power reading from Power Meter.
5. Change VAC from 108VAC to 132VAC and perform “4”.
6. Refer to Section 7.2 for shutdown procedure.
7.2 Equipment Shutdown
1. Turn off equipment.
2. Make sure capacitors are discharged.
7.3 Phase Angle Decode vs LED Current (at dimming)
1. Connect LV5012MD-A19-120VEVM like upper Figure4. An external LED load must be used
to start up the EVM.
2. Prior to turning on the AC source, set the voltage to 120VAC.
3. Monitor the Dimmer output AC voltage between the neutral and the line by using the
oscilloscope differential probe.
4. Turn on the AC Source.
5. Maximize the dimmer ratio.
6. Record the output voltage readings from Volt Meter and the output current reading from
AMP Meter. And Record the input power reading from Power Meter. And Record the phase
angle of Dimmer output reading from the oscilloscope differential probe.
7. Gradually lower the Dimming ratio and perform "6". Repeat it until the Dimming ratio is
minimized.
8. Refer to Section 7.2 for shutdown procedure.
8. Performance Data
8.1 Efficiency
Efficiency vs Input Voltage
87
50Hz
86
60Hz
Efficiency [ % ]
85
84
83
82
81
80
79
78
77
100
110
120
130
140
Input Voltage [ VAC ]
Figure5. Efficiency vs Input voltage
8.2 Power factor
Power Factor vs Input Voltage
1.00
50Hz
60Hz
Power Factor
0.98
0.96
0.94
0.92
0.90
0.88
0.86
100
110
120
130
Input Voltage [ VAC ]
Figure6. Power factor vs Input voltage
140
8.3 Line regulation
LED Current (Output current)
LED Current vs Input Voltage
600
50Hz
590
60Hz
LED Current [ mA ]
580
570
560
550
540
530
520
510
500
100
110
120
130
140
Input Voltage [ VAC ]
Fgure7. LED current vs Input voltage
Output Voltage
Output Voltage vs Input Voltage
20.5
50Hz
20.4
60Hz
Output Voltage [ V ]
20.3
20.2
20.1
20.0
19.9
19.8
19.7
19.6
19.5
100
110
120
130
Input Voltage [ VAC ]
Figure8. Output voltage vs Input voltage
140
8.4 Input voltage/current operation waveform (No dimming)
CH1
Input voltage (VAC)
[100V/div]
CH4
Input current
[200mA/div]
5msec/div
Figure9. Input waveform
8.5 Output voltage/current operation waveform (No dimming)
CH1
Output voltage
[5V/div]
CH4
Output current
(LED current)
[200mA/div]
5msec/div
Figure10. Output waveform
8.6 Switching operation waveform
CH1
Q1 Drain voltage
[100V/div]
CH4
Q1 current
[500mA/div]
10usec/div
Figure11. Switching operation waveform
8.7 LED Current vs Phase angle
[ Measurement condition: V AC=120V, 60Hz, Dimmer= LEVITON IPI06 ]
LED Current vs Phase angle
600
LED Current [mA]
500
400
300
200
100
0
0
20
40
60
80 100 120 140 160 180
phase angle [ deg ]
Figure12. LED current vs Phase angle
8.8 Dimming operation waveform
[ Measurement condition: V AC=120V, 60Hz, Dimmer= LEVITON IPI06 ]
Phase angle = 120 degree
CH1
Input voltage
=Dimmer output
[100V/div]
CH4
Input current
[200mA/div]
5msec/div
Figure13. Dimming operation waveform at phase angle=120degree
Phase angle = 60 degree
CH1
Input voltage
=Dimmer output
[100V/div]
CH4
Input current
[200mA/div]
5msec/div
Figure14. Dimming operation waveform at phase angle=60degree
8.9 EMI data
Conducted Emission
QP Measurement
[ Measurement condition: VAC=120V,60Hz ]
Phase1
Phase2
Figure15. Conducted Emission, QP Measurement
9. Board Layout
Figure16. Transformer Side Layout
Figure17. IC Side Layout
Figure18. Board Size
10.Bill of materials
No
Designator
Description
Value
Footprint
Manufacturer
Manufacturer Part Number
1
2
3
4
5
6
7
8
9
10
12
13
14
15
16
17
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
41
42
43
44
C1
C2
C3
C4
C5
C7
C8
C9
C10
C11
C12
D1
D3
D4
D5
F1
L1
L2
Q1
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
R12
R14
R15
R16
R17
R18
R19
R20
T1
U1
VR1
Metallized Polyester Film Capacitor
Capacitor,Ceramic,X7R
Capacitor,Ceramic,X7T
Capacitor,Ceramic,X7R
Capacitor,Ceramic,X7R
Capacitor,Ceramic,CH
Capacitor,Ceramic,X7R
Capacitor,Ceramic,X7R
Aluminum Electrolytic Capacitor
Capacitor,Ceramic,E
Capacitor,Ceramic,X7R
Diode,Bridge
Diode
Diode,Ultrafast
Diode,Schottky
Metal Film Fuse Resistor
Jumper
Power Inductor
N-Channel Power MOSFET
Metal Film Resistor
Metal Film Resistor
Metal Film Resistor
Jumper
Chip Resistor
Chip Resistor
Chip Resistor
Chip Resistor
Anti-surge Chip Resistor
Anti-surge Chip Resistor
Jumper
Chip Resistor
Metal Film Resistor
Jumper
Chip Resistor
Chip Resistor
Low Ohmic Chip Resistor
Low Ohmic Chip Resistor
Anti-surge Chip Resistor
Transformer
LED Driver
Varistor
0.033uF/275VAC
0.1uF/630V
0.33uF/450V
0.1uF/630V
2.2nF/630V
150pF/50V
0.1uF/50V
1uF/25V
1000uF/35V
2.2nF/250VAC
4.7uF/50V
0.8A,600V
0.2A,250V
1A,400V
4A,200V
10,1W
0
1.0mH
500V,2.6A
15,2W
15,2W
1k,1W
0
390k
3.3k,1%
270k
10k,1%
1.0k
12k
0
4.7Meg
100k,1W
0
22
100k
1.2,1%
0.91,1%
27k
Radial
Radial
Radial
Radial
1206
0603
0603
0603
Radial
Radial
1206
1Z(SMD)
SOD-123
SMA
SMC
Axial
Radial
DPAK
Axial
Axial
Axial
1206
0603
1206
0603
1206
1206
0603
0603
Axial
0603
0603
0603
0805
0805
1206
RM6
MFP14S
Radial
OKAYA
MURATA
MURATA
MURATA
MURATA
MURATA
MURATA
MURATA
Rubycon
MURATA
MURATA
SHINDENGEN
ON Semiconductor
ON Semiconductor
ON Semiconductor
Panasonic
Sumida
ON Semiconductor
Panasonic
Panasonic
Panasonic
Rohm
KOA
Rohm
KOA
Rohm
Rohm
KOA
Panasonic
Panasonic
KOA
KOA
KOA
Rohm
Rohm
Rohm
WE-Midcom
ON Semiconductor
Nippon Chemi-con
LE333
RDER72J104K8K1C11B
RDED72W334K5B1C13B
RDER72J104K8K1C11B
GRM31BR72J222KW01L
GRM1882CH1H151JA01
GRM188R71H104KA93D
GRM188R71E105KA12D
35ZLH1000
DE1E3KX222MA4BL01
GRM31CR71H475KA12L
S1ZB60
MMSD103T1G
MURA140T3G
MBRS4201T3G
ERQ1ABJ100
RCH895NP-102K
NDD03N50Z
ERG2SJ150
ERG2SJ150
ERG1SJ102
KTR18EZPJ394
RK73H1JTTD332
KTR18EZPJ274
RK73H1JTTD103
ESR18EZPJ102
ESR18EZPJ123
RK73Z1JTTD000
ERJ3GEYJ475V
ERG1SJ104
RK73Z1JTTD000
RK73B1JTTD220
RK73B1JTTD104
MCR10EZHFL1R20
MCR10EZHFLR910
ESR18EZPJ273
750341533 Rev.04
LV5012MD
TND05V-271KB
AC175V
11.Transformer specification
12.Detailed Descriptions for Application Circuit Setting
The LV5012MD-A19-120VEVM04 is the isolated flyback converter with phase cut dimming. The explanation of each parts of the application
circuit is described in figure19. How to set this application circuit is described below.
AC1
R1
F1
10/1W
Snubber circuit for TRIAC dimming
15/2W
R3
1k/1W
AC INPUT
VR1
C1
0.033uF
/AC275V
AC2
R2
15/2W
C4
0.1uF
/630V
Filter for EMI and TRIAC dimming
Snubber circuit
D1
S1ZB60
R4
L2
0
1.0mH
C2
0.1uF
/630V
R14
100k
/1W
C5
C3
0.33uF/450V
2.2nF
/630V
D4
MURA140
L1
Transformer
Secondary side
rectifier diode
T1
F
1
0
D3
Filter for EMI and TRIAC dimming
Resistors
for ALC function
R5
390k
R9
1.0k
R7
Capacitor
for VIN supply
R10
12k
U1
270k
C12
4.7uF
/50V
MMSD103
HV
OUT
DML
GND
2
Resistor
for bleeder
current
Resistors
for TRIAC ON/OFF detection setting
and bleeder current setting
3
4
NC
VIN
GND
CS
ENB
REF_IN
ACS
TRC
5
Transformer T1 specifications
Inductance value
1-3 inductance Lp = 0.7mH
S-F inductance Ls = 32uH
Turns ratio
(4-6) : (S-F) = 1 : 1.14
C7
150pF
R6
3.3k
R8
10k
R11
7
R20
27k
C10
6
1000uF
/35V
0
4
S
LED-
R16
14
R17
100k
13
22
Q1
NDD03N50
R12
12
Capacitor
for smoothing output voltage
Power
MOSFET
4.7Meg
11
C11
10
6
LED+
3
R15
LV5012MD
1
D5
MBRS4201
2
Auxiliary winding
for VIN supply
Start up resistor
for HV regulator
(6 LEDs in series)×2parallel
[LED: NICHIA
NS6W083AT]
2.2nF/AC250V
9
REF_OUT
ALC_C
8
C8
C9
0.1uF
1uF
0
Capacitor
for ALC function
R18
1.2
R19
0.91
Current sense resistor
Figure19. The description of each parts of LV5012MD-A19-120VEVM04
Capacitor
for noise reduction
12.1 Transformer design
At first calculate about primary inductance and secondary inductance.
The primary inductance Lp is calculated
(VAC peak) 2 × Dp2 × η × 0.565
Lp =
2 × POUT × f
where,
Lp : Primary side inductance
VAC peak : Input peak voltage
η : Conversion efficiency of transformer
f : Switching frequency = 70k [Hz]
POUT : Output power of secondary side
Transformer
current
Is peak
Primary
current
Secondary
current
Ip peak
POUT = VOUT × IOUT
VOUT : Output voltage (LED voltage)
IOUT : Output current (LED current)
Dp : Duty of primary side current
Tp
Dp = T
Time
Tp
Ts
T
Figure20. Transformer current
Tp : Time of primary side current
T : Switching period = 1/70k [sec]
The secondary inductance Ls is calculated
(VOUT + Vf ) 2 × Ds 2
Ls = L × (I peak) 2 × f 2
p
p
Transformer
LED+
Rectified AC voltage
where,
Ls : Secondary side inductance
Vf : Forward voltage of the rectifier diode
Lp
[Turns: Np]
Ip peak : Peak current of Primary side inductance “Lp”
(*Refer to section “12.3”)
Ds : Duty of secondary side current
Vf
Ls
[Turns: Ns]
[Turns: Nd]
LED-
Ts
Ds = T
Ts : Time of secondary side current
Figure21. Transformer Turns
Next calculate about Turns Raito by primary inductance and secondary inductance.
Np
Ns =
Lp
Ls
where,
Np : Turns of primary side
Ns : Turns of secondary side
Design the most suitable transformer with the winding turns ratio and the inductance value.
Confirm that the operation with the designed transformer is a current discontinuous mode.
The auxiliary winding turns Nd is calculated
Nd
VIN
=
Ns
VOUT
where,
Nd : Turns of auxiliary winding
VIN : VIN pin voltage
12.2 REF_IN pin and ALC_C pin setting
 R5, R6 setting
Please set R5, R6 so that the voltage peak of the REF_IN pin is around 1.1V to 1.9V.
e.g. VAC=120V → R5=390kΩ, R6=3.3kΩ
REF_IN peak = (120V×√2) × 3.3k / (390k+3.3k) = 1.42V
 C8 setting
Please connect capacitor of about 0.1uF to an ALC_C pin.
By the above setting, ALC function of LV5012MD becomes effective. Thereby the application of
LV5012MD can achieve good line regulation and total harmonic distortion.
12.3 CS pin setting
 R18, R19 setting
The output power of second side is set by the current sense resistor (R18, R19) connected to
CS pin. The current sense resistor is calculated,
0.141 × Lp × f × η
2 × POUT
R18 × R19
R18 + R19 =
Figure22 is the operation outline diagram.
Rectified
AC voltage
LV5012MD
inside
ALC_out
Auto
Level
Control
VREF
(0.45Vtyp)
+
CLK
Q
RESET
Lp
Q1 current
(Primary side current)
ALC_out
OUT
VREF
(0.45Vtyp)
Q1
Q1
current
0.5Vtyp
Reference
CS
T
R18
R19
ON
OUT
(Q1 Gate)
OFF
Ton
Toff
Reference=ALC_out
Reference
=0.45V
Figure22. Operation outline diagram (No dimming)
The peak current of Lp “Ip peak” is the following expression.
R18 + R19
Ip peak = R18 × R19 × 0.45
( In the case of ALC_out > VREF(0.45V) )
Reference=ALC_out
12.4 ACS pin and DML pin setting
LV5012MD contains the function for TRIAC dimming. This function is operated by setting ACS
pin and DML pin.
Figure23 is the outline diagram of TRIAC dimming operation.
Please set the TRIAC ON/OFF threshold and the Bleeder operation threshold in tune with the
characteristic of TRIAC dimmer. The TRIAC ON/OFF threshold and the Bleeder operation
threshold are calculated as follow.
The TRIAC ON threshold of the rectified AC is determined below.
R7 + R8
Vac_triac on =
× 1.7
R8
The TRIAC OFF threshold of the rectified AC is determined below.
R7 + R8
Vac_triac off =
× 1.3
R8
The Bleeder operation threshold of the rectified AC is determined below.
R7 + R8
× 0.85
R8
Vac_bleeder =
Please set R7, R8 on the basis of these expressions according to TRIAC dimmer.
In addition, please set R9 between the rectified AC voltage and DML pin to satisfy the following
expression.
 R7 + R8

× 0.85  - ( R9 × 0.02 ) < 50 [V]
 R8


Rectified
TRIAC OUT
Rectified
AC voltage
ACS
Rectified AC voltage
Bleeder
current
R9
0.85V +
ACS
+
Auto
Level
Control
0.85V
T
Built-in MOSFET
for Bleeder current
Bleeder MOS gate
Lp
ALC_out
CLK
-
1.7V
1.3V
LV5012MD
inside
-
R7
Q
RESET
0.1V
-
1.3V
R8
1.7V
DML
VREF
(0.45Vtyp)
+
TRIAC ON
OUT
TRIAC OFF
ALC_out
Q1
Q1
current
VREF
(0.45Vtyp)
CS
R18
Q1 current
(Primary side
current)
Reference
R19
0.1V
T
TRIAC OFF
TRIAC ON
TRIAC
OFF
Bleeder MOS gate
Bleeder MOS ON
Bleeder MOS OFF
Figure23. Outline diagram of TRIAC dimming operation
Bleeder
MOS ON
12.5 HV pin setting
 R10 setting
LV5012MD has a high voltage regulator built-in for self-supplying from the rectified AC voltage. It
outputs 12V, and thereby the circuit in the IC starts. Please connect R10=12kΩ between HV pin
and the rectified AC voltage to operate HV regulator normally.
12.6 Protection function
1
2
3
4
Tilte
UVLO
OCP
OVP
OTP
Outline
Under Voltage Lock Out
Over Current Protection
Over Voltage Protection
Over Temperature Protection
monitor point
VIN voltage
CS voltage
VIN voltage
PN Junction temperature
1. UVLO(Under Voltage Lock Out)
If VIN voltage is 7.3V or lower, then UVLO operates and the IC stops. When UVLO operates,
the power supply current of the IC is about 80uA or lower. If VIN voltage is 9V or higher, then the IC
starts switching operation.
VIN
voltage
VIN
voltage
UVLOON
(9Vtyp)
UVLOOFF
(7.3Vtyp)
time
Output stage
on
off
on
2. OCP(Over Current Protection)
CS pin is used to sense current in primary winding of transformer via external MOSFET. This
provides an additional level of protection in the event of a fault. If the voltage of the CS pin exceeds
VCSOCP(1.9Vtyp.)(A), the internal comparator will detect the event and turn off the MOSFET. The
peak switch current is calculated
Iocp(peak)[A] = VCSOCP[V] / Rcs[Ω]
The VIN pin is pulled down to fixed level, keeping the controller latched off. The latch reset occurs
when the user disconnects LED from VAC and lets the VIN falls below the VIN reset
voltage,UVLOOFF(7.3Vtyp.)(B). Switching restarts when VIN rises UVLOON(9Vtyp.)(C).
CS
voltage
A
C
VCSOCP(1.9Vtyp)
time
VIN
voltage
B
UVLOON(9Vtyp)
UVLOFF(7.3Vtyp)
time
Output stage
on
off
on
3. OVP(Over Voltage Protection)
If the voltage of VIN pin is higher than the internal reference voltage VINOVP(27Vtyp), switching
operation is stopped. The stopping operation is kept until the voltage of VIN is lower than
VINOVP(27Vtyp). If the voltage of VIN pin is lower than VINOVP(27Vtyp), the switching operation
is restated. Pease see OVP waveform chart.
OVP
VIN
voltage
OVP release
27Vtyp
time
Output stage
on
off
on
4. OTP(Over thermal protection)
LV5012MD has the gradually thermal protection system. If the junction temperature exceeds 140
degrees Celsius, 1st stage protection mode is started. At 1st stage protection mode, the internal
reference level compared with CS pin voltage is set to 0.1V. And the LED current is restricted to
low values (approximately 5%).
If the junction temperature exceeds 155 degrees Celsius, the switching operation and startup
circuit are stopped. Please see OTP waveform chart.
155℃
143℃
140℃
IC
Junction
Temperature
128℃
Time
100%
LED Current
Normal
Condition
Normal
Condition
1st Stage
Thermal
Protection
Normal
Condition
Thermal
Shut
Down
Time
Approximately
5%