This document provides specifications and design details for a 100W LED power supply using Fairchild semiconductor components. The power supply uses a BCM PFC controller and boost follower for wide input voltage range of 80-310VAC. A 2-switch flyback converter provides constant current or constant voltage output to 1 or 4 LED channels. Control and protection ICs are also detailed to balance current across multiple LED strings.

1. www.fairchildsemi.com1
Steve Mappus,
March 08, 2013
100W, PFC, CCCV, 4-Channel, LED Power Supply

2. www.fairchildsemi.com2
100W PFC, LED Power Supply Specification
Primary Design Goals
1. Wide Input 80VAC<VIN<310VAC
2. Maximize Wide Range Efficiency
3. Configurable for Single Channel or 4-Channel LED
Operation
4. Compatible with 0V-10V Analog Dimming and 0%-100%
PWM Dimming
5. Lowest Possible Design Profile
Intended Application
1. Street, Parking Lot & Highway Lighting
2. Industrial High-Bay Lighting
FL7930C BCM PFC
MIN TYP MAX
VIN_AC 90V 120V 310V
FVIN_AC 50Hz 60Hz 65Hz
VOUT_PFC 440V 450V 460V
VOUT_PFC (Boost Follower) 245V VINPK+40V 470V
VOUT_PFC_RIPPLE 10V
POUT_PFC 120W
FSW_PFC 35kHz 300kHz
tSOFT_START 200ms 250ms
η_PFC_120V 96% 96.5%
η_PFC_230V 97% 97.5%
PF_120V 0.996
PF_230V 0.975
FAN6300H 2-Switch Flyback, CCCV Converter
MIN TYP MAX
VIN 240V 470V
VOUT_LED 30V 62V
POUT 100W
IOUT 2A
FSW 30kHz 120kHz
D 20% 45%
η_250V 94%
η_450V 93%
FAN7346 4 Channel LED Current Balance Controller
VOUT_LED 30V 62V
VOUT_OVR 65V
POUT 87W
IOUT_4CH 0A 350mA/CH
AnalogDIM 13% 100%
PWMDIM 0% 100%
Total System
VIN_AC 90V 120V 310V
FVIN_AC 50Hz 60Hz 65Hz
tSOFT_START 100ms 150ms
η_120V 90% 91%
η_230V 91% 91.6%
PF_120V 0.996
PF_230V 0.975
tR(VOUT) 30ms 50ms
IOUT_4CH 0A 350mA/CH
VOUT_LED 30V 62V
VOUT_OVR 65V
Mechanical and Thermal
Height 24mm
θJC 60⁰C

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Fairchild Featured Content
CONTROLLERS
1. FL7930C, Single Stage Flyback and Boundary-Mode PFC Controller for Lighting
2. FAN6300H, Highly Integrated Quasi-Resonant Current Mode PWM Controller
3. FAN7346, 4-Channel LED Current Balance Controller
4. FSL138MRT, Green-Mode Fairchild Power Switch for High Input Voltage (800V)
GATE DRIVERS
1. FAN7832, HVIC High-Side, Low-Side Gate Driver
2. FAN3111C, Single 1A High-Speed, Low-Side Gate Driver
DISCRETE
1. FCP190N60E, 600V, SuperFET 2, N-Channel MOSFET
2. FDP22N50N, 500V, UniFET 2, N-Channel MOSFET
3. FDT86256, 150V, PowerTrench, N-Channel MOSFET
4. 2N7002K, N-Channel Enhancement Mode Field Effect Transistor
5. ES3J, 600V, 3A, Ultrafast Recovery Rectifier
ANALOG
1. KA431A, Programmable Shunt Regulator
2. FOD817A, High Operating Temperature Phototransistor Optocoupler
3. FAN4274, Dual Rail-to-Rail I/O, CMOS Amplifier
4. LM393, Dual Differential Comparator
5. LM555, Single Timer

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Power Board Partitioning
1 2
3
4
5
6
7
1. AC Input, EMI Filter, Inrush Current Limiting
2. Flyback Bias Regulator
3. BCM PFC
4. 2-Switch Flyback
5. Removable Controller Card (4-Channel Controller Shown)
6. PWM Dimmer Circuits
7. LED Output Terminal Block

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Power Board Dimensions
228.6mm
76.2mm
25mm

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LED Current Controller Cards
OR
4-Channel, 60V, 350mA per Channel Single Channel, 50V, 2A
J19
J23

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FL7930C Features
• VMC with ZCD
• ZVS when VIN<VOUT/2
• 150µs Restart Timer
• 300kHz Frequency Clamp
• 5ms Internal Soft Start
• Cycle-by-Cycle Current Limit
• Open Feedback Protection
• PFC RDY Function
• 8-Pin Small Outline Package
(SOP)
FL7930C
Single Stage Boundary-Mode PFC Controller
VCC
ZCD
VTH(ZCD)
VCC
OUT
+
-
S
QR
Q
+
-INV 1
5
COMP 3
Clamp
Circuit
+
-
VCS_LIM
40kW
8pF
4 CS
0.450.35
disable
2.6752.5
disabl
e
+
-
VZ
+
-
VTH(S/S)
128.5
VO(MAX)
VCC
2.5VREF
Internal
BiasVBIAS
VREF
Gate
Driver
Restart
Tmer
7
8
6 GND
+
-
INV_open
OVP
RDY 2
reset
reset
H:open
Thermal
Shutdown
fMAX
Limit
VREF
Overshoot
Prevention
VREF
Stair
Step
Clamp
Circuit
THD
Optimized
Sawtooth
Generator
VIN Absent
VCC
2.882.5
disable
VREF
Control Range
Compensation
UVLO FL7930C

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FAN6300H Features
• High Voltage Start-Up
• Quasi-Resonant Extended
Valley Detection
• Peak Current Mode Control
• Leading Edge Blanking
• 5ms Internal Soft Start
• Latching OVP (DET)
• Open Feedback Loop
Protection
• Programmable Over Current
Protection
• 8-Pin Small Outline Package
(SOP)
FAN6300H
Quasi-Resonant Current Mode PWM Controller
CS
8 6
2
3
1
4 7
5
0 .3 V
D RV
GND
VDD
Two Steps
UVLO
16 V/10 V/8V
Internal
Bias
Latched
18 V
GATE
DET
FB
NC
HV
Latched
4 .2V
2 R
R
Soft-Start
5 m s
PW M
Current Lim it
ID ET
Internal
OTP
Latched
S/H
Blanking
Circuit
tO FF -MIN
ID ET
5V
DET OVP
2.5V
tO FF
Blanking
Q
Q
S E T
C L R
S
R
FB OLPTim er
52 m s
Over-Power
Com pensation
VD ET
Starter
30 µs
Latched
Valley
Detector
0.3 V
27 V
OVP
V D ET
IH V
tTIME -O U T
2 .1m s

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FAN7346 Features
• Current Sharing Accuracy
Trimmed to 1.5%
• Individual Channel 0% to
100% PWM Dimming
• 0V to 10V Analog
Dimming
• Error Flag Output
• Programmable LED OVP
• Individual Channel Open
LED Protection
• Individual Channel Short
LED Protection
• Individual Channel OCP
• Master Slave Configurable
• 28-Pin SOIC
FAN7346
4-Channel LED Current Balance Controller
OUT1
FB1
FB2
OUT3
OUT2
FB3
OUT4
FB4
CH4
CH3
CH2
CH1
GND
PWM1
FB
VDD
OVR
VREF
+
-
ch1 ch2 ch3 ch4
5V, max. 3mA
UVLO 9.5V
Voltage Reference
& Internal Bias
-
+
Hysteresis 1.0V
1.2V-
+
200k
VCC
ENA
REF
On/Off
ADIM
VLREF=VADIM/10
PWM2
PWM3
PWM4
CMP
-
+
1.42V
OVR
+
-
1V
OCP (latched)
Sampling & Hold
Channel Voltage
at PWM_off
Internal Soft Start: 10ms
Current increases gradually
All Protection disable
(except OCP)
PWM is full duty
8.5V
Feedback Circuit
(Ref = 1V)
Clamped 0.5~4V
PWM On/Off
Rising/Falling Time =
400ns/150ns
400ns 150ns
FO
PWM1
PWM2
PWM3
PWM4
VREF
+
-
+
-
1V
OCP (latched)
VREF
+
-
+
-
1V
OCP (latched)
VREF
+
-
+
-
1V
OCP (latched)
ch# Minimum
Detector
Min.
ch.V/10
SLPR
SLP(20µs count)
+
-
Individual by
each channel
Protection
Control
Block
ch.V
+
-
0.3V
OLP(20µs count)
CH# = 5V
(remove from feedback)
PWM# = off
(reset in PWM# rising edge)
OLP/OCP
SLP/OCP
VMIN
ch1 / ch2 / ch3 / ch4
Enable ON
Enable OFF
0.5V 4.0V
OLP, SLP, OCP Protection
Error Flag

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FSL138MRT Features
• Internal 800V SenseFET
• High Voltage Start-Up
• Internal 15ms Soft Start
• 70kHz Fixed Frequency
• Pulse by Pulse Current
Limit
• 350ns LEB
• Overload Protection
• Overvoltage Protection
• 6-Lead Formed TO-220F
FSL138MRT
Green-Mode, High Input Voltage FPS

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Power Board Schematic
PFC, Boost Follower Enable, Inrush Limit
BOOST FOLLOWER
1. OFF=450V
2. ON=BF
3. OPEN=250V

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Power Board Schematic
2-Switch Flyback, PWM Dimmers

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Power Board Schematic
High-Voltage Flyback Bias Power Supply
• 80VAC<VIN<300VAC
• Primary Referenced, PBIAS~15V, 0.5A
• Secondary Referenced, SBIAS=12V, 0.5A

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Controller Daughter Card Schematic
Single String CCCV LED Controller
• Sources Current into Optocoupler Anode (OPTO_A)
• Constant LED Current set to 2A
• Constant LED Voltage set to 50V

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Controller Daughter Card Schematic
4-Channel LED Controller
• Sinks Current Through Optocoupler Cathode
(OPTO_C)
• Constant LED Current set to 350mA
• Over-Voltage Regulation (OVR) set to 62V
PDIM
1. OFF=5V
2. ON=PWM DIM

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BCM PFC Boost
FL7930, FAN3111C, FCP190N60E, ES3J
BOOST FOLLOWER
1. OFF=450V
2. ON=BF
3. OPEN=250V

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• VIN=115VAC
• VOUT=450V
• POUT=120W
• PF=0.991
BCM PFC AC Input Waveforms
CH2=VIN(AC), CH4=IIN(AC)
• VIN=230VAC
• VOUT=450V
• POUT=120W
• PF=0.979

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• VIN=115VAC
• VOUT=450V
• ZVS; VIN(PK)<VOUT/2
• FS=175kHz
• POUT=120W
BCM PFC Switching Waveforms
CH1=VGS, CH2=VDS, CH4=IL
• VIN=230VAC
• VOUT=450V
• Valley Switching; VIN(PK)>VOUT/2
• FS=250kHz
• POUT=120W

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• VOUT=450V (constant) to cover 80VAC<VLINE<310VAC when the
Boost Follower is not used
• VOUT(BF) tracks VIN for VIN >140VAC when Boost Follower is used
• Boost Follower VOUT=250V to 460V
• Downstream DC/DC Converter Designed for 250V<VIN<460V
BCM PFC Boost Follower
0
50
100
150
200
250
300
350
400
450
500
80 130 180 230 280
Voltage(VDC)
AC Line Voltage (VRMS)
VOUT(PFC)
Vin(pk)
Non BF

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• Benefit to FL7930C PFC
• VIN=120VAC
• VOUT(BF)=250V to 460V
• Combined with DC/DC
Downstream Converter, Boost
Follower Yields about 1%-2%
Efficiency Improvement
BCM PFC Boost Follower Efficiency Benefit
• Benefit to FAN6300H DC/DC
• VIN=VOUT(BF)=250V to 470V
• 250VIN corresponds to 120VAC
• POUT=70W (LED Load)
• Without Boost Follower, VIN=450V
(constant) for 80VAC<VLINE<310VAC
90%
95%
100%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Efficiency(%)
Output Power (%)
FL7930C PFC Efficiency
(120VAC Input, 100%=120W)
Boost Follower
450V
90%
95%
100%
250 270 290 310 330 350 370 390 410 430 450 470
Efficiency(%)
Input Voltage (VDC)
FAN6300H 2-SW Flyback Efficiency
(DC Input, 50V, 4x350mA, 70W)
93.34%,
450V
250VDC=120VAC
94.02%,
250V

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• VIN=Step 115VAC to 300VAC
• VOUT(BF)=250V to 450V
• POUT=60W
BCM PFC Boost Follower Voltage Tracking
CH1=VIN(AC), CH2=VOUT(BF)
• VIN=Step 300VAC to 115VAC
• VOUT(BF)=450V to 250V
• POUT=60W

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• Electronic Load used for POUT of PFC stage only.
• LED Power is constant and should operate within 50%<PPFC<90%
of this PFC stage
BCM PFC Boost Follower PFC stage only
0.80
0.85
0.90
0.95
1.00
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
PowerFactor
Output Power (%)
FL7930C Power Factor
(120W, PFC Section Only)
120VAC
230VAC LED Power Range

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2-Switch Flyback
FAN6300H, FAN7382, FDP22N50N, FOD817A
• FAN6300H Bias comes from FL7930C, RDY Signal
• FAN7382 Bias comes from FSL138MRT, PBIAS Output
• Feedback Control (OPTP_A, OPTO_C) comes from either:
 Single String CCCV LED Controller Card
 FAN7346 4-Channel LED Controller Card

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• VDD Reaches 16V (VDD(ON)) and HV>50V,
Switching Starts and VDD Begins to Fall to
RDY level Bias (12V)
• FB is HIGH (5V) when Switching Begins
• If FB>4.2V for >55ms, Open Feedback
Protection is Enabled and Switching Stops
• VIN(AC)=120VAC
• VIN=VOUT(PFC)=250V
• POUT=70W (50V, 4x350mA)
2-Switch Flyback Start-Up Waveforms
CH1=HV, CH2=VDD, CH3=GATE, CH4=FB or VLED
• LED Output Voltage rises smoothly
with no overshoot
• FS=68kHz
• POUT=70W (50V, 4x350mA)

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• VIN(AC)=120VAC
• VIN=VOUT(PFC)=250V
• D=40%
• FS=65kHz
• POUT=70W (50V, 4x350mA)
2-Switch Flyback Switching Waveforms
CH1=VGS(LO), CH2=VGS(HO), CH3=VCS, CH4=VFB
• VIN(AC)=300VAC
• VIN=VOUT(PFC)=460V
• D=23%
• FS=95kHz
• POUT=70W (50V, 4x350mA)

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• VIN(AC)=120VAC
• VIN=VOUT(PFC)=250V
• D=40%
• FS=65kHz
• POUT=70W (50V, 4x350mA)
• VDS Always Valley Switching for
Constant Load
2-Switch Flyback Switching Waveforms
CH1=VGS(LO), CH2=VDS(LO)
• VIN(AC)=300VAC
• VIN=VOUT(PFC)=460V
• D=23%
• FS=95kHz
• POUT=70W (50V, 4x350mA)
• VDS Always Valley Switching for
Constant Load

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• VDS Valley Switching on First Valley
• VIN(AC)=120VAC
• VIN=VOUT(PFC)=250V
• D=42%
• FS=63kHz
• POUT=85W (60V, 4x350mA)
2-Switch Flyback Switching Waveforms
CH1=VDS(LO), CH3=VGS(LO)
• VDS Extended Valley Switching
• VIN(AC)=120VAC
• VIN=VOUT(PFC)=250V
• D=11%
• FS=68kHz
• POUT=24W (Dim, 60V, 4x100mA)

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• VIN=VOUT(PFC) operating as Boost Follower
• POUT=70W
• VOUT=50V (4-Channels, 18 LEDs per channel)
• IOUT=1.4A (4-Channels, 350mA each)
FAN6300H, 2-Switch Flyback Efficiency
90%
95%
100%
250 270 290 310 330 350 370 390 410 430 450 470
Efficiency(%)
Input Voltage (VDC)
FAN6300H 2-SW Flyback Efficiency
DC Input, 70W (50V, 4x350mA)

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High Voltage, Flyback Bias Regulator
FSL138MRT, FOD817A
• 67kHz Fixed Frequency Operation
• Internal 800V SenseFET
• Supplies Primary Bias (PBIAS) and Secondary Bias (SBIAS) to System

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• VIN(AC)=120VAC
• When VSTR reaches 12V,
Switching Begins
• VSTR must be 26V During
Steady State Switching
High Voltage, Flyback Bias Regulator, Start-Up
CH1=VDS, CH2=VCC or VSTR, CH3=SBIAS, CH4=PBIAS
• VIN(AC)=120VAC
• VCC Supplied from Flyback
Transformer Bootstrap
Winding (PBIAS)

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• VIN(AC)=120VAC
• SBIAS=12V, <100mA
• PBIAS=15V, <100mA
• RDY is generated from PBIAS
and must be > 11V at
FAN6300H VDD
High Voltage, Flyback Bias Regulator, Burst Mode
CH1=VDS, CH2=VCC, CH3=SBIAS, CH4=PBIAS
• VIN(AC)=120VAC
• Always Operates in Burst Mode
(VFB<0.5V) due to Constant
Light Load (POUT<2W)
• Fixed Frequency Operation
Means no VDS Valley Switching

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4-Channel LED Controller
FAN7346, FDT86256
• Sinks Current Through Optocoupler Cathode
(OPTO_C)
• Constant LED Current set to 350mA
• Over-Voltage (OVR) set to 62V
PDIM
1. OFF=5V, (No
PWM Dim)
2. ON=PWM DIM

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• 2V<VDIM(PWM)<5V
• VDIM(OFF)=0.8V
• 100Hz<FPWM<500Hz
• FAN7346 can PWM Dim Each LED Channel Independently
• Demo Includes 2, On-Board PWM Dimmers Operating from 1% to 100% Duty Cycle
• PWM Dimming is linear from 0% (barely on) to 100% (full brightness)
• Full LED-Off at <1% Duty Cycle Requires <0.8V (no pulse), Achievable by µC or Analog Comparator
• FAN7346 Automatically Disables Open LED Protection (OLP) and Short LED Protection (SLP) for any given Channel
during PWM Dimming
FAN7346 PWM Dimming
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
PercentMaxLEDCurrent(%)
PWM Dimming Duty Cycle (%)
PWM Dimming
(120VAC, 250Hz, 3.3VDIM, 50V, 4x350mA, 70W)

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• PWM Dimming “Chops” LED DC Current
• FPWM=250Hz
• DCH1=DCH2=50%, DCH3=10%, DCH4=100%
• ILEDCH1=ILEDCH2=35mA
• ILEDCH3=176mA
• ILEDCH4=350mA
• PIN=35.1W
• POUT=30.5W
• η=87.02%
• PF=.971 during Dimming
FAN7346 PWM Dimming
CH1=PWMCH3, CH2=PWMCH1_CH2, CH3=ILEDCH3, CH4=ILEDCH1_CH2
• 2,On-Board PWM Dimmers, set Power Board
Jumpers J17, J21 to “ON” and set J101, J103,
J104 J105 to “ON”
• PDIM1 Controls Channels 1, 2
• PDIM2 Control Channels 3, 4
• FPWM=250Hz, 1%<D<100%
• VPWM=5V
• Set J17, J21 to “OFF” to disable PWM Dimming
or Apply External PWM Dimming Signal

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FAN7346 Analog Dimming
+
-
VADIM/10
VOUT
Vds
Vf
Vsense
Vg
1V
Cc
Rc
Gm
OVR
FB
VD1
VD2
VD_MIN
COMI
Force power PWM off
Headroom Control Feedback Block
(Min VDx = 1V)
Current Balance Block
LEDx Current = VADIM/(10*Rs)
• Each LED String is Terminated with an External MOSFET and CS (Current Sensing) Resistor
• The Voltage across the CS Resistor is the Inverting Input of an Internal LED Comparator
• The Comparator Reference Voltage is Set by a Scaled (VADIM/10) DC Voltage
• ADIM Voltage is Clamped to 0.5V<VADIM<4V
• When Analog Dimming is not Desired, the Applied ADIM Voltage should be at least 5V (Internally Clamped
to 4V) for Full LED Brightness
• Design Feedback to Control Minimum Drain Voltage to 1V
• Control LED Current of each String by Varying VGS and VDS

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• 0.5V<VADIM<5V
• Analog Dimming Range is 8:1 (4V/0.5V)
• Analog Dimming Function Dims all LED Channels Simultaneously while
Maintaining Equal LED Current Balance
• Can Not Dim to 0% (Full-Off) due to Minimum Internal Analog Dimming
Voltage (VREF) Clamped at 0.5V
FAN7346 Analog Dimming
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
PercentMaxLEDCurrent(%)
Dimming Voltage (VDC)
Analog Dimming
(120VAC, 50V, 4x350mA, 70W)

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• OVR (Over-Voltage Regulation) set to ~52V for 50V, 4x350mA (70W)
Operation to meet 50V Specification
• OVR set to ~62V for 60V, 4x350mA (85W) Operation to allow 100%
Illumination (88 LEDs) of LED Load Module
• VLED(MIN)=31V
FAN7346 CCCV Operation
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
30 35 40 45 50 55 60
OutputLEDCurrent(ADC)
Output LED Voltage (VDC)
CCCV
(120VAC, 50V, 4x350mA, 70WMAX)

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System Performance
• LED Load Module
• AC Input Line Voltage and Current
• Start-Up Bias Sequence
• Inrush Current
• Measured THD
• Measured System Efficiency
• Measured Power Factor

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HB LED Load Module
• 4 Independent LED Strings
• 22, Cree XLAMP, 3A HB LEDs
per String
• 66VMAX per String
• 3AMAX per String (Fan Cooling)
• 4 Configurable Series Strings
(88 LEDs) Supports up to 264V

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Cree XLAMP, 3A HB LED
XMLAWT-00-0000-0000T6051

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• VIN(AC)=120VAC
• VOUT(PFC)=250V
• POUT=70W (50V, 4x350mA)
• PF=0.995
AC Input Line Voltage and Current
CH1=VIN(AC), CH2=IIN(AC)
• VIN(AC)=230VAC
• VOUT(PFC)=400V
• POUT=70W (50V, 4x350mA)
• PF=0.938

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• Start-Up Sequence
• VIN(AC)=120VAC
• VOUT(PFC)=250V
• POUT=70W (50V, 4x350mA)
• PBIAS; FL7930C, FAN7382
• SBIAS; FAN7346
• VOUT(PFC)>0.89×VOUT(PFC), RDY Signal HIGH
• RDY Signal Applies PBIAS to FAN6300H and
Disables Inrush Current Limiter
• VLED Rises, LEDs Illuminate
Bias Sequence
CH1=PBIAS, CH2=RDY, CH3=VOUT(PFC), CH4=VLED
• Shut-Down Sequence
• VIN(AC)=120VAC
• VOUT(PFC)=250V
• POUT=70W (50V, 4x350mA)
• VOUT(PFC)<0.89×VOUT(PFC), RDY Signal LOW
• RDY Signal Disables PBIAS to FAN6300H and
Enables Inrush Current Limiter
• VLED Slowly Discharges

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• NTC R7 and R12 Limit Inrush to 3.18A During Start-Up
• VIN(AC)=120VAC
• VOUT(PFC)=250V
• POUT=70W (60V, 4x350mA)
• PBIAS sets 5VREF (D5) at U1-2, Comparator Output is LOW
• RDY Signal (12V) Applied to U1-3, Comparator Output is HIGH, Relay Shorts Across R7+R12 to Maintain High
Efficiency During Steady State Operation
• Relay Shorting Time can be Further Adjusted by R16, C10
• Relay Short is Removed during Power Supply Turn-Off
Inrush Current Limiting
CH1=VIN(AC), CH2=IIN(AC), CH3=VLED

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• Inrush Circuit Enabled
• VIN(AC)=120VAC
• VOUT(PFC)=250V
• POUT=70W (60V, 4x350mA)
• Peak Inrush Current is 3.18A
• Reduces Inrush Current by 79.15%
Inrush Current Limiting Comparison
CH1=VIN(AC), CH2=IIN(AC), CH3=VLED
• Inrush Circuit Disabled
• VIN(AC)=120VAC
• VOUT(PFC)=250V
• POUT=70W (60V, 4x350mA)
• Peak Inrush Current is 15.25A

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Measured THD
Chroma 61502 Programmable AC Source
0
0.05
0.1
0.15
0.2
0.25
0.3
3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Harmonic
Current(A)
Harmonic Number
EN61000-3-2, 115VAC, 85W (4x350mA)
Measured Harmonic Current
Class C (Lighting) Limit
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Harmonic
Current(A)
Harmonic Number
EN61000-3-2, 230VAC, 85W (4x350mA)
Measured Harmonic Current
Class C (Lighting) Limit
• VIN(AC)=115VAC
• VOUT(PFC)=250V
• POUT=85.41W (60V, 4x350mA)
• PIN=93.8W
• η=91.05%
• THD=8.91%
• Easily Passes EN61000-3-2, Class C, Lighting
Equipment PIN>25W
• VIN(AC)=230VAC
• VOUT(PFC)=400V
• POUT=86.2W (60V, 4x350mA)
• PIN=94.2W
• η=91.51%
• THD=21.52%
• Barely Passes EN61000-3-2, Class C, Lighting
Equipment PIN>25W
• EMI Filter not Optimized

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Measured System Efficiency
• 91.7% Peak Total System Efficiency
includes EMI Filter and Flyback Bias
• Boost Follower PFC shows 1.2% Peak
Efficiency Gain Compared to Fixed Output
PFC
• Slight Drop in High Line Efficiency Caused
by Boost Follower Output Voltage being
470V at VIN(AC)=300VAC, Compared to
450V Fixed PFC Output Voltage
• 91.7% Peak Total System Efficiency
includes EMI Filter and Flyback Bias
• Both Cases Shown Operating with PFC
Boost Follower
85%
90%
95%
80 100 120 140 160 180 200 220 240 260 280 300
Efficiency(%)
Input Voltage (VAC)
Boost Follower Comparison
61V, 4x350mA, 85W
450V
Boost Follower
80%
85%
90%
95%
100%
80 100 120 140 160 180 200 220 240 260 280 300
Efficiency(%)
Input Voltage (VAC)
POUT Comparison
70W, 50V, 4x350mA
85W, 60V, 4x350mA

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Measured System Power Factor
• Peak PF=.996 for Low-Line Voltage
• Boost Follower PFC
• Fixed 450V PFC Output shows Identical
PF verses Input Voltage
• PF>0.9, for entire Range of VIN(AC)
• Boost Follower PFC
• Fixed 450V PFC Output shows Identical
PF verses Input Voltage
0.85
0.90
0.95
1.00
80 100 120 140 160 180 200 220 240 260 280 300
Efficiency(%)
Input Voltage (VAC)
50V, 4x350mA, 70W
0.850
0.900
0.950
1.000
80 100 120 140 160 180 200 220 240 260 280 300
Efficiency(%)
Input Voltage (VAC)
61V, 4x350mA, 85W