MP44011

MP44011
Boundary-Mode PFC Controller
with Harmonic Injection
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP44011 is a boundary-conduction–mode
PFC controller with an internal-harmonic–
injection function. It provides simple and highperformance active power-factor correction with
minimal external components.





Compared
against
traditional
boundaryconduction–mode
PFC
controllers,
the
harmonic-injection function makes the part
suitable for LED lighting applications.





In LED lighting applications with two-stage
structures, the harmonic-injection function can
effectively reduce bus capacitance between the
AC/DC and the DC/DC stage. In addition,
harmonic injection can reduce the transformer
size to save board space and BOM cost.
Boundary-Conduction–Mode PFC Controller
for Pre-Regulation
Reduced Bus Capacitance
Reduced Transformer Size
Internal Harmonic-Injection Function
Precise Adjustable-Output Over-Voltage
Protection
Ultra-Low Start-Up Current
Very Low Quiescent Current
On-Chip Filter for Current-Sense Pin
Disable Function
Available in SOIC-8
APPLICATIONS


Also, the benefits of a harmonic-injection
function also apply to general boost or flyback
PFC applications.
LED Lighting Driver
General PFC Pre-Regulators
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“MPS” and “The Future of Analog IC Technology” are Registered
Trademarks of Monolithic Power Systems, Inc.
Patents pending.
The MP44011 is derived from the MP44010,
except with a harmonic-injection function.
The MP44011 is available in an 8-pin SOIC
package.
TYPICAL APPLICATION
C5
D1
T1
R9
Vbus
C4
C6
D3
R3
D2
D1
DC/DC
R1
R7
C1
R5 C3
VAC
R8
R4
U1
R6
FB
ZCS COMP
VIN MP44011
GATE
MULT
CS
GND
R2
R10
Q1
Feedback
Network
C2
R11
MP44011 Rev. 1.01
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1/12/2012
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© 2012 MPS. All Rights Reserved.
1
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
ORDERING INFORMATION
Part Number
MP44011HS*
Package
SOIC8
Top Marking
Junction Temperature (TJ)
MP44011
-40°C to +125°C
* For Tape & Reel, add suffix –Z (e.g. MP44011HS–Z).
For RoHS compliant packaging, add suffix –LF (e.g. MP44011HS–LF–Z).
PACKAGE REFERENCE
TOP VIEW
FB
1
8
VIN
COMP
2
7
GATE
MULT
3
6
GND
CS
4
5
ZCS
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance
Supply Voltage (VIN)......................-0.5V to +23V
Analog Inputs and Outputs .......... -0.3V to +6.5V
ZCS Maximum Current ............-50mA to +10mA
(2)
Power Dissipation (TA=25°C)
SOIC8 ........................................................ 1.4W
Junction Temperature……………………..150°C
Lead Temperature (Solder).......................260°C
Storage Temperature ............... -55°C to +150°C
SOIC8 ..................................... 90 ...... 45 ... °C/W
Recommended Operating Conditions
(3)
Supply Voltage (VIN)....................... 13.4V to 22V
Analog Inputs and Outputs ............. -0.3V to +6V
Operating Junction Temp. (TJ). -40°C to +125°C
(4)
θJA
θJC
Notes:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ(MAX), the junction-toambient thermal resistance θJA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by D(MAX)=(TJ(MAX)TA)/ θJA. Exceeding the maximum allowable power dissipation
will cause excessive die temperature, and the regulator will go
into thermal shutdown. Internal thermal shutdown circuitry
protects the device from permanent damage.
3) The device is not guaranteed to function outside of its
operating conditions.
4) Measured on JESD51-7, 4-layer PCB.
MP44011 Rev. 1.01
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1/12/2012
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© 2012 MPS. All Rights Reserved.
2
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
ELECTRICAL CHARACTERISTICS
VIN = 15V, TA =TJ= 25°C, unless otherwise noted.
Parameter
Supply Voltage
Operating Range
Turn-On Threshold
Turn-Off Threshold
Hysteretic Voltage
Zener Voltage
Supply Current
Start-Up Current
Quiescent Current
Operating Current
Multiplier
Input Bias Current
Linear Operation Range
Output Max. Slope
Gain(5)
Symbol
Condition
Min
VIN
VIN on
VIN off
VIN hys
Vz
After turn on
10.7
11
8.7
2.2
22
Istartup
Iq
IIN
VIN=11V
No switch
Fs =70kHz, CO=1nF
IIN=5mA
IMULT
VMULT
ΔVCS/ΔVMULT
K
0 to 3
1.62
VFB
2.465
Typ
Max
Units
25
22
13.4
10.7
3
28
V
V
V
V
V
15
0.46
1.6
40
0.65
2.5
µA
mA
mA
-1
12.4
9.8
1.85
0.6
0.82
µA
V
V/V
1/V
2.5
2.535
V
2
5
mV
0.2
µA
Error Amplifier
Feedback Voltage
Feedback Voltage Line
Regulation
VFB_LR
Feedback Bias Current
VIN=10.7V to 22V
IFB
(6)
GV
(6)
GB
Open Loop Voltage Gain
Gain-Bandwidth Product
Source Current
60
80
dB
1
MHz
ICOMP_source
-5
-4
Sink Current
ICOMP_sink
2.5
5.5
Upper Clamp Voltage
VCOMP_H
5.3
6
6.6
V
Lower Clamp Voltage
VCOMP_L
2
2.2
2.4
V
-1
450
1.83
µA
ns
V
mV
mV
Current Sense Comparator
Input Bias Current
Delay
Current Sense Clamp Voltage
VCS
Current Sense Offset
VCS_Offset
Zero Current Sensor
Upper Clamp Voltage
ICS
tDT
1.6
Clamp
VZCSclamp
H
VMULT=0V
VMULT=2.5V
IZCS=2.5mA
7.2
300
1.72
30
5
-2
mA
mA
7.8
MP44011 Rev. 1.01
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1/12/2012
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© 2012 MPS. All Rights Reserved.
V
3
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
ELECTRICAL CHARACTERISTICS (continued)
VIN = 15V, TA = TJ=25°C, unless otherwise noted.
Parameter
Lower Clamp Voltage
Zero Current Sensing Threshold
ZCS_EN Threshold
ZCS_EN Hysteresis
Source Current Capability
Restart Current After Disable
Re-Starter
Re-Start Time
Over-Voltage
Dynamic OVP Current
Hysteresis
Static OVP Threshold
Gate Driver
Dropout Voltage
Symbol
VZCSclamp L
VZCS H
VZCS L
VZCS EN R
VZCS EN hys
IZCS source
IZCS res
Condition
Min
Typ
Max
Units
IZCS=-2.5mA
VZCS rising
VZCS falling
VZCS rising
0.3
0.55
2.1
1.35
310
120
0.8
2.3
-85
-3
-60
V
V
V
mV
mV
mA
µA
1.15
tstart
80
175
280
µs
IOVP
IOVP Hys
VOVP
30
40
30
2.2
50
µA
µA
V
VOH
VOL
tf
tr
VD max
Voltage Fall Time
Voltage Rise Time
Max Output Drive Voltage
Source Current Capability
Sink Current Capability
IGate source
IGate sink
UVLO Saturation Voltage
VSaturation
2
IGDsource=20mA
IGDsource=200mA
IGDsink=200mA
12
VIN=0 to VIN_ON,
IGate sink=10mA
2.4
4.8
1.2
30
40
13.5
-350
600
2.4
3
5.4
1.5
70
80
15
V
V
V
ns
ns
V
mA
mA
0.3
V
Note:
5) The multiplier output is given by: Vcs=K·VMUTL·(VCOMP-2.5)
6) Guaranteed by design.
MP44011 Rev. 1.01
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1/12/2012
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© 2012 MPS. All Rights Reserved.
4
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 15V, TA = 25°C, unless otherwise noted.
Supply Current vs.
Supply Voltage
Supply Current vs. TJ
Start-up & UVLO vs. TJ
14
10
100
0.1
VIN THRESHOLD (V)
1
Quiescent Current
1
0.1
0.01
Start-up Current
0.001
0
5
10
15
20
25
0.01
-50
0
50
Rising
13
Operating Current
10
100
12
11
10
Falling
9
8
-50
150
0
50
100
150
VIN (V)
VIN Zener Voltage vs. TJ
Feedback Reference vs. TJ
2.6
500
2.55
400
25
24
VFB(V)
23
2.5
300
2.45
200
22
21
0
50
100
2.4
-50
150
OVP Current vs. TJ
0
50
1.8
1.6
1.4
45
CS (V)
1.2
40
35
1
0.8
150
0
COMP=3.5V
COMP=3V
COMP=2.6V
0
50
100
150
0.8
COMP=5V
0.2
100
0
Multiplier Gain vs. TJ
COMP=4V
COMP=4.5V
0.4
50
100
-50
1
0.6
0
150
Multiplier Characteristic
50
30
-50
100
1
2
3
4
MULTIPLIER GAIN
20
-50
COMP=Upper clamp
VIN ZENER VOLTAGE (V)
26
Delay-to-output vs. TJ
0.6
0.4
0.2
0
-50
0
50
100
150
MULT (V)
MP44011 Rev. 1.01
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1/12/2012
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5
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VIN = 15V, TA = 25°C, unless otherwise noted.
ZCS Clamp Levels vs. TJ
10
400
Upper Clamp
ZCS CLAMP(V)
8
6
4
2
0
-50
Lower Clamp
Gate-drive Output
High Saturation
Gate-drive Output
Low Saturation
800
350
700
300
600
250
500
200
400
150
300
100
200
50
100
0
0
0
50
100
150
2
3
4
5
6
VGD DROPOUT (V)
7
0
1
2
3
4
VGD (V)
MP44011 Rev. 1.01
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1/12/2012
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© 2012 MPS. All Rights Reserved.
6
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
Performance waveforms are generated on the evaluation board built with design example.
VAC=110V, Vbus=70V, IOUT=350mA, POUT=30W, TA=25°C, unless otherwise noted.
MP44011 Rev. 1.01
www.MonolithicPower.com
1/12/2012
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© 2012 MPS. All Rights Reserved.
7
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
PIN FUNCTIONS
Pin #
1
2
Name
FB
COMP
3
MULT
4
CS
5
6
ZCS
GND
7
GATE
8
VIN
Description
Feedback. Connect to the output voltage through a resistor divider.
Error Amplifier Output. Connect a compensation network between this pin and the FB pin.
Multiplier Input. Connect to the rectified main voltage through a resistor divider to provide the
sinusoidal reference for the current control loop. Also senses input AC voltage and injects
constant ratio harmonics
Current Sense. Senses the current through the MOSFET using a resistor. Provides internal
sinusoidal reference when compared with the output of the internal multiplier to determine
MOSFET’s turn-off. On-chip R/C filter reduces high-frequency noise on this pin.
Current-Zero–Crossing Sense. A negative going-edge triggers the MOSFET to turn on.
Ground.
Gate Driver Output. The large gate-driver current can drive the gate of the low-cost highpower MOSFET in the system. The pin voltage is clamped to 15V in case this pin is supplied
with a high VCC.
Supply Voltage. Powers both the signal block and gate driver. Use a bypass capacitor from
this pin to ground to reduce the noise.
BLOCK DIAGRAM
ZCS
Disable
Voltage
regulator
2.1V
1.35V
VIN
Starter
+
UVLO
+
Vref -
Driver
GATE
S Q
R
Overvoltage
detection
GND
+
1.4pF
-
-
Multiplier
FB
+
2.5V
150k
Harmonic injection
generation
CS
MULT
COMP
Figure 1: Functional Block Diagram
MP44011 Rev. 1.01
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1/12/2012
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8
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
APPLICATIONS
The MP44011 is a boundary-conduction–mode
PFC controller with internal harmonic injection
that is optimized for LED lighting drivers.
Output Voltage Regulation
The FB pin senses the output voltage through a
resistor divider from the output voltage to ground.
An accurate on-chip reference voltage and a
high-performance error amplifier accurately
regulate the output voltage.
Over-Voltage Protection
MP44011 offers two of over-voltage protection
methods: dynamic and static. These two
methods ensure that the circuit operates in a
reliably safe region.
When the load is very low, the output voltage
tends to stay steadily above the nominal value.
Under this condition, the error amplifier output
saturates low. When the error amplifier output
falls below 2.2V, the static OVP triggers and
blocks the gate driver to turn off the external
power MOSFET and enter an idle state. Normal
operation resumes until the error amplifier output
goes back into the regulated region.
UVLO
Driver
GATE
Vo
IR9
Overvoltage
detection
R9
If there is an abrupt rise on the output (ΔVO), the
voltage on FB pin remains at the reference value
as the compensation network between FB pin
and COMP pin features a long time-constant for
a high power factor (PF). The current through
R10 remains equal to VFB/R10, but the current
through R9 becomes:
'
IR9

VO  VO  VFB
R9
The current must flow into the COMP pin. At the
same time, the chip internally monitors the
current. If the current rises to 35µA, the output
voltage of the multiplier decreases, thus reducing
the the energy delivered to output. If the current
rises to about 40µA, the dynamic OVP triggers.
Then gate driver is blocked to turn off the
external power MOSFET and the MP44011
enters an idle state. The device will remain in this
state until the current falls below 10µA. Then the
internal starter is re-enabled and allows switching
to restart.
Disable Function
Pulling the zero current sensing (ZCS) pin lower
than 190mV disables to MP44011 in order to
further reduce the quiescent current when the
PFC pre-regulator needs to be shutdown. After
releasing the ZCS pin, it will stay at lower clamp
voltage if there is no external voltage from the
auxiliary winding.
INV
Boundary Conduction Mode
-
Multiplier
+
2.5V
IR10
R10
Vaux
COMP
ZCS
Figure 2: OVP Detector Block
For the boost PFC application, MP44011
implements OVP by monitoring the current
through the COMP pin.
In steady-state operation, the current flows
through the high-side feedback resistor (R9) and
low-side feedback resistor (R10) are:
IR9 
VO  VFB
V
 IR10  FB
R9
R10
Disable
2.1V
1.35V
starter
+
Driver
GATE
S Q
R
Figure 3: ZCS, Triggering, and Disable Block
MP44011 Rev. 1.01
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9
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
When the inductor current reaches zero, the
inductor voltage reverses. Then the ZCS
generates the turn-on signal for the MOSFET by
sensing the falling edge of the voltage on the
auxiliary winding coupled with the inductor. If the
ZCS voltage goes higher than 2.1V, the
comparator waits until the voltage falls below
1.35V. If the voltage falls below 1.35V, the
MP44011 turns on the MOSFET. The 7.8V high
clamp and 0.55V low clamp protect the ZCS pin.
The internal timer generates a MOSFET turn-on
signal if the driver signal is low for more than
175µs, and can turn on the MOSFET during
start-up since there is no ZCD signal is
generated during this period.
Zero-Crossing Compensation
The MP44011 offers a 30mV voltage offset for
the multiplier output near the line votlage’s zerocrossing that can force the circuit to process
more energy at the bottom of the line voltage.
This function reduces the total harmonic
distortion (THD) of the current.
To prevent excess energy consumption, this
offset reduces as the instantaneous line voltage
increases so that the offset is negligible near the
top of the line voltage.
Harmonic Injection Function
D2
Vb u s
The flyback PFC application exemplifies the
harmonic injection function for this document. For
a traditional BCM flyback PFC, the transformer
acts like two coupled inductors where the current
will not flow through both windings at the same
time; the current is discontinuous. The primary
current rises from the zero crossing and the
secondary current returns to zero for every
switching cycle. The average input current is
related to both the peak primary current and the
duty cycle.
Peak Primary Current
Average Primary Current
Primary Current
Figure 6: Primary Current Waveform of
Flyback PFC with the MP44011
For the MP44011, the MULT pin senses the AC
input line and injects constant ratio harmonics
into sensed line voltage, so the peak primary
current reference has a choppy sinusoidal signal.
As a result, the peak primary current flowing
through the transformer is sharply reduced, and
the circuit can use a smaller transformer core
that will not saturate.
T1
D1
Cbus
C1
V ac
Q1
Rs
Figure 4: Flyback PFC Main Circuit
Peak Primary Current
Primary Current
Average Primary Current
In addition, harmonic injection into the input
current reduces the input power fluctuation: This
results in a smaller output voltage ripple on the
output capacitor, and allows for the use of
smaller capacitors. Therefore, the MP44011’s
internal harmonic injection function can reduce
both bus capacitor values and transformer size.
However, there is a trade-off between smaller
core and performance: a smaller core can have
more winding layers and therefore greater
leakage inductance. This leakage reduces
efficiency and increase device voltage stress..
Figure 5: Primary Current Waveform of
Traditional BCM Flyback PFC
MP44011 Rev. 1.01
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1/12/2012
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10
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
Swithing frequency
Frequency of traditional
BCM flyback PFC
Frequency of
MP44011
0
t
A rectified AC voltage and COMP voltage
generates the multiplier output, which generates
the inductor current envelope. Place a small
ceramic capacitor from the MULT pin to S-GND
and place compensation components close to
the COMP pin and S-GND to improve noise
immunity.
For zero-current sensing, place R5 close to the
ZCS pin to prevent noise caused by long wire.
Tline/2
Figure 7: Switching Frequency
Even with the same transformer core as used for
a traditional BCM PFC, the efficiency improves
with harmonic injection.
With harmonic injection, the minimum frequency
occurs not at the top of the line but at the line’s
choppy regions. Compared with traditional BCM
PFC, the frequency at the top of the line
increases.
Power Factor Correction
For inductor current sensing, keep the trace from
the current-sensing resistor to the CS pin pin as
short as possible—even though there is an onchip filter on the CS pin—to prevent falsely
turning off MOSFET. If the design bars the use of
a short trace, add an external filter from the
sense resistor to the CS pin. To prevent noise
from P-GND, limit the connection between PGND and S-GND to one point.
To keep the chip operational with a stable VIN
voltage, keep the VIN capacitor as close to the
VIN pin to limit voltage fluctuations.
The MP44011 senses the inductor current
through the current sense pin and compares it to
the choppy sinusoid signal which is generated
from the multiplier output. When the external
power MOSFET turns on, the primary inductor
current rises linearly. When it reaches the choppy
sinusoid signal, the external power MOSFET
turns off and the secondary diode turns on. Then
the secondary inductor current begins to fall.
When the secondary inductor current reaches
zero, the power MOSFET turns on again, which
causes the primary inductor current to start rise .
The power circuit works in boundary conduction
mode and inductor current’s signal envelope has
a choppy sinusoidal shape. The average current
also has a choppy sinusoidal shape. This control
method can achieve a high power factor.
Layout Guide
For boundary-mode PFC operation, the output
feeds back to the FB pin for comparison with the
reference voltage. Therefore, a constant
reference voltage is very important for an
accurate output. Use short traces to connect the
FB pin to the feedback resistors.
MP44011 Rev. 1.01
www.MonolithicPower.com
1/12/2012
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© 2012 MPS. All Rights Reserved.
11
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
DESIGN EXAMPLE FOR FLYBACK
For MP44011, the coefficient K1 is the peak
PFC WITH MP44011
primary-current
1. Design Specifications:
Input voltage range:
VAC=85V-265V
fL=50Hz
Typical mains frequency:
DC output voltage:
VOUT=70V
Maximum output power:
POUT=30W
with
the
traditional CRM PFC. Here, K1=0.87.
2.2 RMS Primary Current:
F2(K V  K 2 )
=0.53A
3
IRMSp =IPKp 
ΔVO=28V peak-to-peak
Minimum switching frequency:
IPKs =
fmin=40kHz
K2=0.75
Harmonic injection ratio:
Leakage inductance overvoltage:
2  POUT
=4.29A
VOUT  K V  F2(K V )
2.4 RMS Secondary Current:
VR=210V
Reflected voltage:
IRMSs =IPKs 
ΔV=100V
Expected efficiency:
η=85%
F3(K V )
=1.03A
3
Power Stage Design
3. Diode Bridge
2. Preliminary Calculations:
The maximum input RMS current is:
Minimum Input Peak Voltage:
IAC _ max 
VPKmin=VACmin× 2 =120V
Maximum Input Peak Voltage:
VPKmax=VACmax× 2 =375V
PIN=POUT/η=35.3W
Peak-to-Reflected Voltage Ratio:
Kv=VPKmin/VR=0.57
Characteristic functions value:
0.5+1.4  10-3  K V
F2(K V )=
1+0.815  K V
F3(K V )=
0.424+5.7  10-4K V
1+0.862  K V
F4(K V )=
0.25-1.5  10-3  K V
1+1.074  K V
2.1 Peak Primary Current
IPKp 
compared
2.3 Peak Secondary Current:
Maximum 2fL output ripple:
Maximum Input Power:
ratio
2K1  Pin
 1.51A
VPKmin  F2(K V )
Pin
VAC_min
 0.42(A)
To provide a sufficient margin, select GBU406
(600V/4A).
4. Input Capacitor
By setting the coefficient r to 0.1, obtain the input
capacitance by using the equation below:
Cin =
IAC_max
2π  fmin  r VAC _ min
 0.19  106 (F)
Use a 0.22μF tantalum capacitor with a 630V
voltage rating as the input capacitor to provide
high-frequency energy during switching cycle.
5. Transformer
Calculate the primary Inductance using the
following:
Lp =
VPKmin  K 2
=1.0mH
(1+K 2  K V )  fmin  IPKp
MP44011 Rev. 1.01
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1/12/2012
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12
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
The turn ratio is:
7. Secondary Diode
n=
VR
=3
VOUT
Then Ap is:
A p =A e  A w =
LP  IPKp  IRMSp
Bmax  K c  j
The maximum RMS current of the output diode is:
IDrms_max =IRMSs =1.03A
And the maximum reverse voltage is:
 1.27  109 mm4
VDmax =
VPKmax
 VOUT  194V
n
Where:
UF3004 (400V/3A) meets the design criteria.
Ae is the effective area of the core section;
8. Output Capacitor
Aw is the effective area of the core window;
Bmax is the max swing of the magnetic flux density
(generally Bmax=0.3~0.4T);
Kc is the window coefficient, which is about 0.3 in
design;
j is the current density of the wire, which is
typically 4-6A/mm2.
The EE25 core is selected according to Ap.
The primary inductor turn number is:
Np 
Lp  IPKp
Bmax  A e
 110
The needed air gap is:

Np 2  A e  
LP
 6.08  10 4 m
And the secondary winding turn number is:
Ns 
Np
n
 36
6. MOSFET
The maximum drain voltage is:
VDSmax =VPKmax  VR  ΔV=685V
The maximum RMS MOSFET current is:
IQrms_max =IRMSp =0.53 A
And the pulse-drain current is:
IQ_pulse >IPKp =1.51A
The FQPF8N80C (800V/8A) meets the power
requirement of the design.
The output capacitor is selected only based on
output voltage ripple
COUT =
F4(K V ) IOUT
1


 K 3  38F
2  π  fL F2(K V ) ΔVO
Where K3=0.85.
The cap (47μF/100V) is selected as the bus
capacitor.
9. Sense Resistor
Assuming a peak value of 2.5V (@VAC_max=265V)
on the multiplier input, the peak value at the
minimum line voltage is VMULTpkmin=2.5 ×
85/265=0.8V which is multiplied by the maximum
slope of the multiplier, 1.62, giving a 1.32V peak
on the current sense. So the sense resistor will
not exceed:
Rsen 
1.32
 0.87
IPKp
Considering the power consumption, select a
0.4Ω sense resistor.
The first stage of flyback PFC design is complete.
Our evaluation board adds two channels of
DC/DC using the MP4689 to constitute a system
for the LED driver. For MP4689 applications,
please find MP4689 datasheet for details.
Figure 8 shows the application schematic with
power stage design. The typical performance and
circuit waveforms are shown in the typical
performance characteristics section. For more
possible applications of this device, please refer
to related Evaluation Board Datasheets.
MP44011 Rev. 1.01
www.MonolithicPower.com
1/12/2012
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© 2012 MPS. All Rights Reserved.
13
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
C5
R9
D1
GBU406
T1
C4
DC/DC
MP4689
C6
47uF
D3
R3
D2
D1
UF3004
R1
R7
Vac
R5 C3
C1
EMI Filter
R6
U1
ZCS
VIN
COMP
FB
R10
Q1
FQPF8N80C
MP44011 GATE
MULT GND
CS
R2
DC/DC
MP4689
R8
R4
0.22uF
Feedback
Network
C2
R11
0.4Ω
Figure 8: Design Example of 30W LED Lighting with MP44011
MP44011 Rev. 1.01
www.MonolithicPower.com
1/12/2012
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© 2012 MPS. All Rights Reserved.
14
MP44011 – BOUNDARY-MODE PFC CONTROLLER WITH HARMONIC INJECTION
PACKAGE INFORMATION
SOIC8
0.189(4.80)
0.197(5.00)
8
0.050(1.27)
0.024(0.61)
5
0.063(1.60)
0.150(3.80)
0.157(4.00)
PIN 1 ID
1
0.228(5.80)
0.244(6.20)
0.213(5.40)
4
TOP VIEW
RECOMMENDED LAND PATTERN
0.053(1.35)
0.069(1.75)
SEATING PLANE
0.004(0.10)
0.010(0.25)
0.013(0.33)
0.020(0.51)
0.0075(0.19)
0.0098(0.25)
SEE DETAIL "A"
0.050(1.27)
BSC
SIDE VIEW
FRONT VIEW
0.010(0.25)
x 45o
0.020(0.50)
GAUGE PLANE
0.010(0.25) BSC
0o-8o
0.016(0.41)
0.050(1.27)
DETAIL "A"
NOTE:
1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN
BRACKET IS IN MILLIMETERS.
2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH,
PROTRUSIONS OR GATE BURRS.
3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH
OR PROTRUSIONS.
4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING)
SHALL BE 0.004" INCHES MAX.
5) DRAWING CONFORMS TO JEDEC MS-012, VARIATION AA.
6) DRAWING IS NOT TO SCALE.
NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third
party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not
assume any legal responsibility for any said applications.
MP44011 Rev. 1.01
www.MonolithicPower.com
1/12/2012
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2012 MPS. All Rights Reserved.
15