DN05072/D
Design Note – DN05072/D
125W Hi-PF Single Stage LED Driver
Device
Application
Input Voltage
Output Power
Topology
I/O Isolation
NCL30001
LED Driver
85 – 265 V ac
125W
CCM Flyback
Yes
Output 1
Output Current
Ripple
Nominal Voltage
Max Voltage
Min Voltage
Typical Power Factor
Typical THDi
Typical Efficiency
Cooling Method /
Supply Orientation
Single stage power converters offer a cost
effective way to provide power for LED
applications with high input power factor and low
THD. The most common CrM or Critical
Conduction Mode solutions are typically limited
to about 50 watts due to high peak currents
characteristic of this approach. A CCM or
Continuous Conduction Mode flyback converter
offers higher power with reduced peak current
while still providing high power factor and very
low THD. This Design Note outlines modifying
ON Semiconductor’s NCL30001 CCM solution
described in Application Note AND8470
extending the output power up to 125 watts. The
standard evaluation board is the basis for this
design.





Input range: 85 – 265 V ac
Output current: 2.5 A
Output voltage: 48 V typical
Efficiency: 88%
Power Factor: >0.98
April 2015, Rev. 0
>0.98
< 6%
>88 %
Free Air
A photo of the modified evaluation board is
shown below:
Circuit Description
The design guidelines for this LED driver are
shown below:
2.5 A
560 mA p-p
48 V
55 V
16 V
Design
The design process begins using the NCL30001
design worksheet found at ON Semiconductor’s
website. Directions for using this worksheet are
described in the first tab. The design started by
entering design guidelines on tab ‘Step1’.
Progressing through tabs as directed, the critical
changes to the standard evaluation board are
noted below and highlighted in the Bill of
Materials at the end of this document:
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1
DN05072/D
Multiple resistors will be used to create the
proper value. Start with the original value of 0.1
 R19 = 39k
ohms for R26, and place a second 0.1 ohm
 R12 = 71.5k
surface mount resistor (R26A) across the
 C20,21,22 = 2200 uF
appropriate traces on the bottom of the board.
Lastly, change C34 from a capacitor to a 0.2
Increasing the power level requires adjustments
ohm resistor resulting in an equivalent resistance
outlined above. In particular, the output filter
of 0.04 ohms. Note that a filter capacitor like
capacitance was increased to reduce ripple due
C34 is not always required across low
to higher output current.
inductance resistors.
 T1 280 µH
 R26A = 0.1 ohm
 ‘C34’ = 0.2 ohm
The design worksheet also specified a power
transformer with 280 µH inductance and a
The PWM dimming function was not required for
primary to secondary turns ratio of 2.24. A new
this solution and therefore removed. In order to
transformer is detailed at the end of this design
maintain functionality, Q5 and Q7 should be
note meeting the requirements with a larger core
bypassed with wire from drain to source. The
to process the increased power. The turns ratio
changes are highlighted below:
was adjusted slightly to optimize fitting the wire
in the bobbin. The transformer is available from
 Z5 = Not Fitted
Wurth Electronik as detailed in the BOM.
 Q5 = Bypassed
 Q7 = Bypassed
 F1 = 3.15 Amp
 Q6 = Not Fitted
Current rating of the fuse must be increased to
 C33 = Not Fitted
accommodate higher input current. Heatsinks for
 R37 = Not Fitted
switching MOSFET Q1 and output rectifier D8
 R38 = Not Fitted
were increased to maintain device temperature
 R39 = Not Fitted
with free-air cooling conditions. D7 voltage rating
 R40 = Not Fitted
should be increased as well.
 R41 = Not Fitted
 R44 = Not Fitted
The output current is measured by a sense
resistor and used by U3B to establish the current
Additionally, the primary Over Voltage Protection
regulation feedback point. The formula for output
circuit was not used. Changes shown below:
current is shown below:




Iout = (Vref * R31) / (R32 * Rsense)
This can be rearranged to solve for Rsense:
Rsense = (Vref * R31) / (R32 * Iout)
Summary
Noting that Vref = 2.5 V as supplied by U3 pin 3
and R31 = 2.7k, R32 = 68k, and the desired
output current is 2.5 A:
Rsense = (2.5 * 2.7k) / (68k * 2.5) = 0.0397 ohm
April 2015, Rev. 0
C8 = Not Fitted
R5 = Not Fitted
D9 = Not Fitted
Z2 = Not Fitted
After modifications, the NCL30001 evaluation
board met all of the design goals. Detailed
performance is outlined on the following pages
along with a schematic and Bill of Materials.
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DN05072/D
Performance
3
91%
2.5
90%
2
89%
1.5
88%
Current
1
87%
Efficiency
0.5
Efficicney (Percent)
Output Current (Amps)
Output current regulation and efficiency across the input voltage range of 85 to 265 V ac is shown below.
Typical current was 2.43 amps with a variation of less than 0.1%. Efficiency is above the 88% target.
86%
0
85%
85
105
125
145
165
185
205
225
245
265
Input Voltage (V ac)
1.00
10
0.99
9
0.98
8
0.97
7
Power Factor
60Hz PF
0.96
6
50Hz PF
60Hz THDi
0.95
5
50Hz THDi
0.94
4
0.93
3
0.92
2
0.91
1
THDi (Percent)
Shown below are Power Factor and input current THD over the input voltage range for 50 and 60 Hz.
0
0.90
85
April 2015, Rev. 0
105
125
145
165
185
Input Voltage (V ac)
205
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225
245
265
3
3.0
90%
2.5
88%
2.0
86%
84%
1.5
Iout
Efficiency
Iout (Amps)
DN05072/D
The converter provides constant current output over a wide range of output operating voltage. Efficiency
is above 86% for loads greater than 50 watts. Performance is shown below.
Efficiency
1.0
82%
0.5
80%
78%
0.0
15
20
25
30
35
40
Vout (Volts)
45
50
55
60
IEC 61000-3-2 Class C data is shown below for 100 V ac 50 Hz input and 2.43 A at 48 V load. The driver
is well below the maximum allowed limits:
30
Harmonic Current Percentage of Fundametal
(%)
25
20
15
10
Limit (%)
Measured (%)
5
0
2
3
5
7
9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Harmonic
April 2015, Rev. 0
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4
DN05072/D
Primary Schematic1
April 2015, Rev. 0
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5
DN05072/D
Secondary Schematic2
April 2015, Rev. 0
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6
DN05072/D
3
MAGNETICS DESIGN DATA SHEET
Project / Customer: NCL30001 Demo Part Description: 125 Watt 50V 2.5A LED Driver
Inductance: 280uH
Bobbin Type: 12 pin vertical
Core Type: PQ3535Core Gap: Gap for 280uH, ~0.028 inches
Winding Number / Type
Step Winding
Start
1
½Primary
1
2
Insulate
3
Secondary 7,8
4
5
6
7
8
Insulate
½Primary
Insulate
Pri Bias
Insulate
Finish
3
11,12
3
2
5
6
Turns / Material / Gauge / Insulation Data
Turns Material
Notes
14
•• #26 TEX-E
Wind bifilar in one layer
2
Mylar Tape
13
•• #24
Wind bifilar in one layer,
terminate one wire per pin
2
Mylar Tape
14
•• #26 TEX-E
Wind bifilar in one layer
1
Mylar Tape
7
#26 TEX-E
Spread evenly in one layer
3
Mylar Tape
Hipot: 3KV from primary to secondary for 1 minute.
April 2015, Rev. 0
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DN05072/D
4
Bill of Materials
Designator
Description
Manufacturer
Manufacturer Part Number
D5, D10
D1, D2, D3,
D4
D6
D7
D9
D11, 12, 13
D8
Diode
ON Semiconductor
MRA4007T
Diode
Ultrafast diode
Ultrafast diode
Signal diode
Signal diode
UFR diode
ON Semiconductor
ON Semiconductor
Micro Commercial
ON Semiconductor
ON Semiconductor
1N5406
MURS160
ES1M-TP
MMSD4148A
MURH860CTG
Z1
Z4
Z5
Z3
Z2
Q5
Q7
Q1
Q2, Q3
Q6
Q4
U1
U2
U3
TVS
Zener diode
Zener diode
Zener diode
Zener diode
Jumper
Jumper
Mosfet
BJT
BJT
BJT
PFC controller
Optocoupler
Dual amp + zener
ON Semiconductor
ON Semiconductor
Infineon
ON Semiconductor
ON Semiconductor
ON Semiconductor
Vishay
ON Semiconductor
1.5KE440A
MMSZ5245B
MMSZ5248B
SPP11N80C3
MMBTA06LT1G
MJD243G
NCL30001
H11A817 or SFH6156A-4
NCS1002
C1, C2
C27
C3
X caps
Y2 cap
Polyprop. Film
C7
Disc cap
0.47 uF, 277
Vac
2.2 nF, 1kV
0.22uF (630V)
68 to 100 nF,
400V
Evox Rifa/Kemet or EPCOS
Evox Rifa/Kemet
Vishay
PHE840MB6470MB16R17 or B32922C3474M
PME271Y422M or P271HE222M250A
2222 383 20224
TDK
FK22X7R2J104K
C15, 16, 25,
C26, C29
C8, C33
C23, C24
C28, C30
C19
C12
C9
C10, C18,
C31
C14, C17,
C32
C13
C5
C11
C6
C20, 21, 22
C4
C35
ceramic cap
0.1 uF, 50V
TDK
C3216X7R2A104K
ceramic cap
ceramic cap
ceramic cap
ceramic disc cap
ceramic cap
ceramic cap
Not Fitted
0.1 uF, 100V
1.0 uF, 25V
1 nF, 1 kV
470 pF, 50V
680 pF, 50V
TDK
TDK
TDK
Vishay
Kemet
C3216X7R2A104K
C3216X7R1H105K
CK45-B3AD102KYNN
VJ1206A471JXACW1BC
C1206C681K5GACTU
ceramic cap
1 nF, 100V
Kemet
C1206C102K1RACTU
ceramic cap
ceramic cap
electrolytic cap
electrolytic cap
electrolytic cap
electrolytic cap
electrolytic cap
ceramic cap
10 nF, 50V
33 nF, 50V
100 uF, 35V
4.7 uF, 25V
220 uF, 50V
2200 uF, 63V
22 uF, 450V
0.1 uF, 50V
TDK
TDK
UCC
UCC
UCC
Nichicon
Nichicon
TDK
C3216COG2A103J
C3216COG1H333J
ESMG350ELL101MF11D
ESMG250ELL4R7ME11D
ESMG500ELL221MJC5S
UPW1J222MHD
647-UVY2W220MHD
C3216X7R2A104K
0.25W resistor
0.5W resistor
0.5W resistor
0.2 ohms
2.2K
1M, 0.5W
Rohm Semiconductor
Vishay
Vishay
MCR18EZHFLR200
NFR25H0002201JR500
CMF601M0000FHEK
C34
R4
R1
April 2015, Rev. 0
Value
Not Fitted
Input transient
option
15V
Not Fitted
18V
Not Fitted
#26 bus wire
#20 bus wire
11A, 800V
60V, 500 mA
Not Fitted
100V, 4A
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8
DN05072/D
R8
R2
R27
R24
R20, R26
R26A
R3
R23
R5
R38
R21, 42, 43
R41
R15, R28
R31, R36
R29,R30
R25
R32
R33
R37
R34
R35
R14, 22
R39, 40, 44
R13
R9
R12
R17
R18
R19
R16
R10
R6, 7, 11
F1
L1A/B
L2
0.5W resistor
0.5W resistor
0.5W resistor
0.5W resistor
0.5W resistor
1W resistor
3 or 5W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
0.25W resistor
Fuse
EMI inductor
EMI inductor
T1
J1, J2, J3
(for Q1, D8)
Flyback xfmr
I/O connectors
Heatsink Q1, D8
HD1
Header
JMP1
Shorting Jumper
2K, 0.5W
560K
4.7K
100 ohms
0.1 ohms
0.1 ohms
36K to 39K
4.7 ohms
Not Fitted
Not Fitted
10 ohms
Not Fitted
2.2K
2.7K
43.2K
20K
68K
6.2K
Not Fitted
82K
3.9K
10K
Not Fitted
7.32K
30.1K
71.5K
Not Fitted
49.9K
39.2K
100K
332K
365K
3.15A, 250Vac
220uH, 2A
50V, 125W
CCM
CONN
HEADER 2POS
0.1" Two
Position
Shorting
Jumper
Vishay
Vishay
Vishay
Vishay
Ohmite
Vishay/Dale
Ohmite
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Vishay/Dale
Littlefuse
Coilcraft
Coilcraft
WE-Midcom (Wurth
Electronics)
Weidmuller
Ohmite
CMF552K0000FHEB
HVR3700005603JR500
CRCW12104K70JNEA
CMF50100R00FHEB
WNCR10FET
WSL2512R1000FEA
PR03000203602JAC00
CRCW12064R75F
CRCW120610R0F
CRCW12062211F
CRCW12062741F
Molex
90120-0122
Sullins Connector
Solutions
SPC02SYAN
CRCW12062002F
CRCW12066812F
CRCW12066191F
CRCW12068252F
CRCW12063921F
CRCW12061002F
CRCW12064322F
CRCW12063012F
CRCW12067152F
CRCW12064992F
CRCW12063922F
CRCW12061003F
CRCW12063323F
CRCW12063653F
37213150001
PCV-0-224-03L
P3220-AL
750314494, REV 00
1716020000
EA-T220-64E
1
© 2015 ON Semiconductor.
Disclaimer: ON Semiconductor is providing this design note “AS IS” and does not assume any liability arising from its use; nor
does ON Semiconductor convey any license to its or any third party’s intellectual property rights. This document is provided only to
assist customers in evaluation of the referenced circuit implementation and the recipient assumes all liability and risk associated
with its use, including, but not limited to, compliance with all regulatory standards. ON Semiconductor may change any of its
products at any time, without notice.
Design note created by Jim Young, e-mail: james.young@onsemi.com
April 2015, Rev. 0
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