Design a

1
CM6805/CM6806/CM6903/CM6201
Design a Champion AC Adapter
Jeffrey H. Hwang
2
CM6805/CM6806/CM6903/CM6201
Two Sources
Champion and FairChild
3
CM6805/CM6806/CM6903/CM6201
Cost Reduction by 0.30 to 0.20
With CM6805, CM6806, CM6903 vs. CRM PWM
4
CM6805/CM6806/CM6903/CM6201
If the Microprocessor Is the brain of the
system, then the Power Supply is the heart.
5
CM6805/CM6806/CM6903/CM6201
High Density AC Adapter
The Challenge High Efficiency at Low Line
(90VAC)
6
CM6805/CM6806/CM6903/CM6201
Typical Power vs. Efficiency
7
CM6805/CM6806/CM6903/CM6201
High Density AC Adapter
8
CM6805/CM6806/CM6903/CM6201
How to increase the Efficiency? (Rule of Thumb)

• Full Load due to Conduction Loss I x I x R
• Spend more money to reduce R such as reduce Rdson
  of Mosfet
• Reduce I by increasing VIN
• Light Load due to Switching Loss fsw x C x V x
  V
• Reduce C
• Reduce V ZVS
• Reduce fsw gt Green Mode

9
Full Load Condition Analysis
Failure Rate Vs. Temperature
10
Full Load Condition Analysis
It is desired to have a uniform Surface
Temperature for Convection and Radiation
By Proper Layout/Package/Enclosure
11
Full Load Condition Analysis
Maximum Power Dissipation vs. Shape
By Proper Layout/Package/Enclosure
12
Full Load Condition Analysis
The Maximum Output Power vs. Shape
h , Po
h , Po
By Proper Layout/Package/Enclosure
13
Full Load Condition Analysis
Use the better Core Shape
Due to the smooth surface, it has the better heat
convection
By Proper Layout/Package/Enclosure
14
Full Load Condition Analysis
A Good AC Adapter Layout
Keep the temperature uniform through out the board
By Proper Layout/Package/Enclosure
15
Full Load Condition Analysis
36W Fly Back AC Adapter Experimental Result
FLYBACK
Design a Flyback Converter
16
Full Load Condition Analysis
36W Fly Back AC Adapter Experimental Result
?85.6 _at_ 90VAC with full load
FLYBACK
Design a Flyback Converter
17
Full Load Condition Analysis
How To Improve Flyback Transformer Power Loss?
FLYBACK

• Reduce the n, Turn Ratio to reduce the Secondary
  Peak Current
• When n ,Ip ,Is , D , Lm , Ls , then
  Maximum Secondary Voltage .
• When n , Ip , Is , D is , Lm , Ls
  ,then Maximum Secondary Voltage .
• 2. Increase the Flyback input voltage
• 3. Use the better RM core instead of EPC core

Design Flyback Converter
18
Full Load Condition Analysis
How To Improve Flyback Transformer Power Loss?
FLYBACK
Design Flyback Converter
19
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
FLYBACK

• Increase the Flyback input Voltage
• Use SR, Synchronous Rectification DCM
• Reduce the secondary current by reducing n, the
  turn ratio of Transformer (This will increase
  Mosfet Loss.)

Design a Flyback Converter
20
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
FLYBACK
Use a Synchronous Rectifier
Design a Flyback Converter
21
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
FLYBACK
CCM Synchronous Rectification has the lower
efficiency due to Trr, body diode recovery issue
Design a Flyback Converter
22
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
FLYBACK
CCM Synchronous Rectification has Trr, body
diode recovery issue
Design a Flyback Converter
23
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
FLYBACK
CCM Synchronous Rectification has Trr, body
diode recovery issue
Design a Flyback Converter
24
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
DCM Efficiency vs. Input voltage
FLYBACK
86, Efficiency _at_ 200V, Vin
CCM Synchronous Rectification has Trr, body
diode recovery issue
Design a Flyback Converter
25
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
FLYBACK

• Solution
• Use DCM SR, Synchronous Rectifier Vin gt200V
  Reduce n

CCM Synchronous Rectification has Trr, body
diode recovery issue
Design a Flyback Converter
26
Full Load Condition Analysis
How To Reduce Flyback Diode Rectifier Power Loss?
Solution Use DCM SR, Synchronous Rectifier
Vin gt 200V Reduce n
FLYBACK
CCM Synchronous Rectification has Trr, body
diode recovery issue
Design a Flyback Converter
27
Full Load Condition Analysis
How To Improve Flyback MOSFET Power Loss?
FLYBACK

• Increase the Flyback input voltage so conduction
  loss can be reduced due to D drops.
• Using DCM to prevent the Trr, diode reverse
  current issue
• Use a lower Rdson Mosfet
• Use ZVS

Design Flyback Converter
28
Full Load Condition Analysis
Conventional Flyback Converter
FLYBACK
LC tanks C is due to S1 and It is very small,
so Ring frequency (resonant frequency) is high.
Design Flyback Converter
29
Full Load Condition Analysis
Conventional Flyback Converter
resonant f is high so it is difficult to control
(manufacture control) it.
FLYBACK
Ip
Vds, S1
The Energy Stored in leakage inductor is wasted
in the ringing.
Design Flyback Converter
30
Full Load Condition Analysis
ZVS Flyback Converter Active Clamp
FLYBACK
LC tanks C is due to Cclamp1uF and It is
relative big, so Ring frequency (resonant
frequency) is lower.
Design Flyback Converter
31
Full Load Condition Analysis
ZVS Flyback Converter Active Clamp
FLYBACK
No Ring and ZVS
The energy is stored in the core release to the
input
Design Flyback Converter
32
Full Load Condition Analysis
ZVS Flyback Converter Active Clamp
FLYBACK
No Ring and ZVS
Design Flyback Converter
33
Full Load Condition Analysis
ZVS Flyback Converter Active Clamp
4.5 Improvement
FLYBACK
Design Flyback Converter
34
Full Load Condition Analysis
ZVS Flyback Converter Active Clamp

• 4.5 Improvement due to
• Energy in leakage L and Snubber is saved
  (Clamped)
• Energy in Vds-parasitic capacitor is saved (ZVS)

FLYBACK

• However, it is expensive
• It needs a high side driver, an extra high side
  Mosfet
• and a simple control circuit
• Can we do it without additional cost?

Design Flyback Converter
35
Full Load Condition Analysis
ZVS Flyback Secondary Synchronous Rectifier with
CM6201 (smart driver)
FLYBACK
LC tanks C becomes to Co/(n x n)25uF to
50uF and It is big, so Ring frequency (resonant
frequency) is very low.
Design Flyback Converter
36
Full Load Condition Analysis
ZVS Flyback Secondary Synchronous Rectifier with
CM6201 (smart driver)
FLYBACK

• Benefits
• It does not need high side driver and high side
  mosfet
• Synchronous Rectification at DCM
• Fly back full load Efficiency is increased
• from
• 86 to90 at Flyback input200V

Design Flyback Converter
37
Full Load Condition Analysis
Summary designing Flyback Converter _at_ full load
Vin200V

• Without additional cost Efficiency87.5 _at_Full
  load
• Vin gt 200V (with PFC-PWM combo
  CM6805/06/CM6903). ?? 3
• n, turn ratio 5 or 6.Reduce Is peak current
• Full load at DCM but approach to CCM.remove Trr
• ZVS by controlling LC variation.??1.5
• With additional cost Efficiency93 _at_Full load
• Secondary Synchronous Rectifier ZVS (CM6201)
• Total additional ? 0.3 at high volume.
  ??2
• RM core
• ? 0.2 at high volume.. ??1.5
• ZVS Active Clamp at primary side.? 0.8 with
  ??2

FLYBACK
Without the proper design, efficiency could be
below 80.
Design Flyback Converter
38
Full Load Condition Analysis
Choose Follower Boost Inductor CM6805 family vs.
CRM, 6561

• L ?, Efficiency ?
• For CRM, 6561, it cannot increase boost
  inductance.
• L?, frequency needs to go lower and it can go
  below 20Khz
• TonL / Rload for a given load, Ton is a
  constant
• L 471uH cannot go higher for the Po 100W
• Ipeak Iin Peak x 2 (I x I x R is big
  efficiency is poor!)
• At high line and light load, frequency can go
  above 400Khz (EMI issue is severe.)
• For CM6805/CM6806/CM6903 fixed switching
  frequency67.5Khz,
• Lcm6805 family Lcrm (67.5khz) x 5 (Optimal
  Inductance Value)
• Lcrm 209uH _at_ 90VAC
• Loptimal 1050 uH _at_ 100W to L 698 uH _at_150W
• L ?, Efficiency ?
• Both the cost of Boost Mos and Boost Rectifier
  can be reduced
• Efficiency (CCM) Efficiency (CRM) gt 3 (total
  system)

Design a Follower Boost PFC
39
Full Load Condition Analysis
Boost Power Dissipation Breakdown
?91.37, Vin90VAC, Po1KW
Boost PFC
2
1
MOSFET
MOSFET
Boost 400V Cap
MOSFET
Design a Follower Boost PFC
40
Full Load Condition Analysis
?91.37, Vin90VAC, Po1KW
Boost PFC
Design a Follower Boost PFC
41
Full Load Condition Analysis
Power Dissipation in Boost Diode
Boost PFC
Design a Follower Boost PFC
42
Full Load Condition Analysis
Power Dissipation in Boost Mosfet
Boost PFC
Dominated One
Design a Follower Boost PFC
43
Full Load Condition Analysis
Boost PFC
4.5 Improvement
Design a Follower Boost PFC
44
PFC Boost with 380V only
Full Load Condition Analysis
Boost PFC
Design a Follower Boost PFC
45
Continuous Boost Follower
Full Load Condition Analysis
4.5 Improvement.cost0.03
Boost PFC
Added Circuit
VlineDC needs to be closed to Dc and gt 5V.
Design a Follower Boost PFC
46
Two Level Boost Follower (Q1 on, 200V _at_ low line
and Q1 off 380V _at_ high line)
Full Load Condition Analysis
4.0 Improvement.cost0.02
Boost PFC
Added Circuit
VlineDC _at_ high line will turn off Q1 and _at_ low
line will turn on Q1.
Design a Follower Boost PFC
47
Two Level Boost Follower or Continuous Boost
Follower
Full Load Condition Analysis
Boost PFC
4.0 to 4.5 Efficiency Improvement.cost0.02
to 0.03
Design a Follower Boost PFC
48
Full Load Condition Analysis
PFC Boost Rectifier Trr issue
Boost PFC
Design a Follower Boost PFC
49
Full Load Condition Analysis
Use SiC to solve PFC Boost Rectifier Trr issue
Boost PFC
??1 ?1.0
Design a Follower Boost PFC
50
Full Load Condition Analysis
SiC will help if the frequency is high.
Boost PFC
Design a Follower Boost PFC
51
Full Load Condition Analysis
Use Soft Switching to solve Trr issue
Boost PFC
Design a Follower Boost PFC
52
Full Load Condition Analysis
Use Soft Switching to solve Trr issue
Boost PFC
??2 ?1.3
Design a Follower Boost PFC
53
Full Load Condition Analysis
Bridgeless PFC
Boost PFC
Design a Follower Boost PFC
54
Full Load Condition Analysis
Bridgeless PFC
Boost PFC
??1......?0.5
Design a Follower Boost PFC
55
Full Load Condition Analysis
Boost PFC
Efficiency Improved due to LETE
Design a Follower Boost PFC
56
Full Load Condition Analysis
Boost PFC
Efficiency Improved due to LETE
Design a Follower Boost PFC
57
Full Load Condition Analysis
CM68XX
Boost PFC
CM68XX
? -0.1 at no cost??1 with LETE
Design a Follower Boost PFC
58
Full Load Condition Analysis
Summary design a Boost PFC _at_ full load and
Vin90Vac

• Without Cost Efficiency95.5 _at_full load
• 2 level Boost Follower(200V/380V).??4
• CM6805/CM6806/CM6903. ??1

Boost PFC

• With Cost Efficiency97 _at_full load
• SiC. ?1.0 and ??1
• Soft Switching. ?1.0 and ??1
• Bridgeless PFC. ?1.0 and ??1

Design a Follower Boost PFC
59
Full Load Condition Analysis
Summary Design a Champion AC Adapter _at_ Full Load
and Vin90Vac

• Without Additional Cost (CM6805/CM6806/CM6903)
• Efficiency84.4 _at_full load Vin 90VAC
• ? pfc x ? flyback 96.5 x 87.5 84.4

• With ?0.3 (CM6201)
• Efficiency86.85 _at_full load Vin 90VAC
• ? pfc x ? flyback 96.5 x 90 86.85

• With ?3.3
• Efficiency90.7 _at_full load Vin 90VAC
• ? pfc x ? flyback 97.5 x 93 90.7

Design a Follower Boost PFC
60
Build-in-Green-Mode CM6805/CM6806/CM6903
Green Mode
The Best Way to Save Energy is to Turn Off Your
Appliance
Green Mode
Light Load Efficiency ?, Goes up, as fpwm?, Goes
down
61
Build-in-Green-Mode CM6805/CM6806/CM6903
Green Mode
Green Mode
User Defined GMth, Green-Mode Threshold
Light Load Efficiency ?, Goes up, as fpwm?, Goes
down
62
Build-in-Green-Mode CM6805/CM6806/CM6903
CM6805/CM6806/CM6903 Build-In Green Mode Functions

• Reduce the switching frequency when the load is
  light
• Turn off PFC _at_ GMth
• Bleed Resistor can be 2 Mohm or higher
• without influence the turn-on time
• Reduce operating current

Green Mode
Light Load Efficiency ?, Goes up, as fpwm?, Goes
down
63
Build-in-Green-Mode CM6805/CM6806/CM6903
Green Mode
Green Mode
Light Load Efficiency ?, Goes up, as fpwm?, Goes
down
64
Build-in-Green-Mode CM6805/CM6806/CM6903
Pulse Skipping from the controller
The Timing Diagram of fRtCt 2 x fPWM 4 x
fPFC in CM6805, CM6806 and CM6903
fRtCt
Green Mode
fpwm CM6806
fpwm CM6805
fPFC
Light Load Efficiency ?, Goes up, as fpwm?, Goes
down
65
Build-in-Green-Mode CM6805/CM6806/CM6903
PWM Green Mode Pulse Skipping Timing Diagram
Green Mode
70K Hz/
70K Hz/
70K Hz/
Light Load Efficiency ?, Goes up, as fpwm?, Goes
down
66
Build-in-Green-Mode CM6805/CM6806/CM6903
Turn Off PFC! When Load is below Green Mode
Threshold, GMth
Green Mode
Light Load Efficiency ?, Goes up, as V? fpwm?,
Goes down
67
Build-in-Green-Mode CM6805/CM6806/CM6903
Po100W Design for VI pin and PWMtrifault
Green Mode
Light Load Efficiency ?, Goes up, as V? fpwm?,
Goes down
68
Build-in-Green-Mode CM6805/CM6806/CM6903
Spread Sheet for the PWM Design for a FlyBack
Green Mode
Light Load Efficiency ?, Goes up, as V? fpwm?,
Goes down
69
Build-in-Green-Mode CM6805/CM6806/CM6903
Increase Start-Up Resistor above 2M ohm without
Increasing Turn-On Time
Green Mode
Light Load Efficiency ?, Goes up, as Rac ?,V?
fpwm?
70
Build-in-Green-Mode CM6805/CM6806/CM6903
Green Mode
Light Load Efficiency ?, Goes up, as Rac ?,V?
fpwm?
71
Build-in-Green-Mode CM6805/CM6806/CM6903

• RAC functions
• Serve as a Start-Up Resistor
• Feed-forward input Sine wave for PFC
• Leading-edge-modulation-PFC-current-loop slope
  compensation
• Power Limit

Green Mode
Light Load Efficiency ?, Goes up, as Rac ?,V?
fpwm?
72
Build-in-Green-Mode CM6805/CM6806/CM6903
Improve Efficiency _at_ Light Load

• CM6805/CM6806
• Reduce PWM switching frequency by pulse skipping
• Turn Off PFC _at_ Green-Mode Threshold, GMth
• Increase Start-Up resistor, RAC gt 2M ohm

Green Mode
_at_ No Load, Pinlt0.3W
Light Load Efficiency ?, Goes up, as Rac ?,V?
fpwm?
73
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903 PFC - FlyBack AC
Adapter Controller
74
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
PFC Start Up then PWM Start Up
75
PFC Soft Start with PWM Soft Start
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
Soft Start for both PFC and Flyback
76
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
Speed up the PFC Voltage Loopby 3X
Fast PFC Voltage Loop
77
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
Error AmplifierTransconductance Amp, GM vs.
Operational Amp, OP
Fast PFC Voltage Loop
78
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
Transconductance Amp, GM vs. Operational Amp, OP
Input Impedance Zin?
Output Impedance, Zout ?
Zin High
Transconductance Amp, GM
Zout High
Input Impedance Zin ?
Output Impedance, Zout ?
Zin High
Operational Amp, OP
Zout Low
Fast PFC Voltage Loop
79
2 Main Purposes of the Error Amp
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903

1. Force V V- and it means Vfb 2.5V
2. Compensation It needs the Rc and Cc

Fast PFC Voltage Loop
80
CM6805/CM6806/CM6903/CM6201
OP Integrator
This local feedback is bad!
CM6805, CM6806 and CM6903
VFB
The Miller Effect slows down the Vfb node. Also,
PFC Voltage Loop is very slow. The consequence
Vfb becomes very slow.
Fast PFC Voltage Loop
81
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
For GM, there is no local feedback. There is only
one outer loop and there is no inner loop. Vfb
is a much faster node.
GM Integrator
Fast PFC Voltage Loop
82
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
GMV (mho)
Iveao (uA)
60uA
69.3u mho
12u/div
12u/div
0uA
-208.6nA
VFB2.51V
-60uA
0
0V
VFB
2.5V
3.0V
Fast PFC Voltage Loop
83
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903
Easy to meet UL1950
84
PFC Features
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903

• Leading Edge Modulation PFC
• Synchronize with Trailing Edge Modulation PWM
• Smaller 400V Bulk Capacitor with 1 better
  efficiency and 30 ripple reduction
• Simplest PFC control, Input Current Shaping
  Technique, ICST (Open Loop Current Mode)
• It works for both CCM or DCM
• Fixed Switching Frequency, fpfc 67.5Khz for
  easy input EMI filter design
• Automatic Slope Compensation with IAC
• Rac at IAC pin serves as a Start-Up Resistor
• 3X PFC Voltage Loop
• PFC has a Tri-fault protections for UL1950
• PFC Soft Start
• PFC OVP VCC OVP
• PFC Current Limit
• Universal Input
• AC Brown Out
• Automatic Turn Off _at_ Green Mode
• Easy to configure into Boost Follower

85
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903

• PWM Features
• Design for FlyBack Converter
• Constant Maximum Power
• Current Mode with inherent slope compensation
• Constant Switching Frequency, fpwm 67.5Khz
  (CM6805 and CM6903), fpwm 135Khz (CM6806)
• Exact 50 maximum duty cycle
• PWM has a PWMTri-fault protections for short and
  Green Mode
• PWMTrifault can be programmed to turn off PFC _at_
  Green Mode
• PWMTrifault can be programmed to detect the short
  or can be programmed to do thermal protection
• PWM has 10 mS digital soft start
• CM6805/CM6806 in 10 pin SOIC packages
• CM6903 in 9 pin SIP package

86
CM6805/CM6806/CM6903/CM6201
CM6805, CM6806 and CM6903

• More Features
• Input Power, Pinlt0.3 W _at_ No Load
• 23V BiCMOS (it can drive IGBT)
• ISTART 100µA
• IOPERATING 2mA without load
• Industry First CM6805/CM6806 PFC-PWM Combo in 10
  pin SOIC packages
• Industry First PFC-PWM Combo CM6903 in 9 pin SIP
  package

87
Input Current Shaping Technique PFC with Leading
Edge Modulation
CM6805, CM6806 and CM6903
CM6903
88
Input Current Shaping Technique PFC with Leading
Edge Modulation
CM6805, CM6806 and CM6903
CM6903
89
Input Current Shaping Technique PFC with Leading
Edge Modulation
CM6805, CM6806 and CM6903

• CM6903

90
Input Current Shaping Technique PFC with Leading
Edge Modulation
CM6805, CM6806 and CM6903

• How does it work?

91
Input Current Shaping Technique PFC with Leading
Edge Modulation
10pin SOIC PFC-PWM combo CM6805/CM6806
92
Input Current Shaping Technique PFC with Leading
Edge Modulation
9pin SIP PFC-PWM combo CM6903
93
Input Current Shaping Technique PFC with Leading
Edge Modulation
Circuit configuration has been modified.
400V Rated Capacitors Can Be Used!
Typical CM6805/CM6806 CM6903 application circuit
94
PWM SECTION
CM6805, CM6806 and CM6903
95
Input Current Shaping Technique PFC with Leading
Edge Modulation PFC Control

• CM6805/CM6806/CM6903 PFC Controller
• Leading Edge Modulation
• with Input Current
• Shaping Technique
• (ICST)

96
Input Current Shaping Technique PFC with Leading
Edge Modulation PFC Control
CM6805, CM6806 and CM6903

• ICST is based on the following equations

(1)
(2)

• Equation 2 means average boost inductor current
  
• equals to input current.
• Assume that input instantaneous power is about to
• equal to the output instantaneous power.

(3)
(4)

• For steady state and for the each phase angle,
  boost
• converter DC equation at continuous conduction
  
• mode is

97
Input Current Shaping Technique PFC with Leading
Edge Modulation PFC Control
CM6805, CM6806 and CM6903

• Rearrange above equations, (1), (2),(3), and (4)
  in term of Vout and d, boost converter duty cycle
  and we can get average boost diode current
  equation (5)

(5)

• Also, the average diode current can be expressed
  as

(6)
98
Input Current Shaping Technique PFC with Leading
Edge Modulation PFC Control
CM6805, CM6806 and CM6903

• If the value of the boost inductor is large
  enough, we can assume

, Id is constant during each switching period,
1/67.5khz.

• It means during each cycle or we can say during
  the sampling, the diode current is a constant.
• Therefore, equation (6) becomes

(7)
99
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation PFC Control
CM6805, CM6806 and CM6903
(8)

• Using this simple equation (8), we implement the
  PFC
• control section of the PFC-PWM controller,
  CM6805, CM6806, CM6903 CM6501

100
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation PFC Control
CM6805, CM6806 and CM6903
Review Leading Edge Modulation Average Current
Mode PFC Control
101
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation
CM6805, CM6806 and CM6903
102
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation
CM6805, CM6806 and CM6903
103
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation
CM6805, CM6806 and CM6903

• 2 purposes to add Isense filter
• Protect IC during inrush current
• Using smaller inductor and still having good THD

Usually, the pole of Isense filter 1/6 of the
switching frequency, and it is 67.5khz/6
1/(2pRfilterCfilter) If Rfilter 1K O,
Cfilter14.15nF.
104
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
105
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
106
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
107
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
108
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
109
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
110
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
111
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
112
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
113
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
For CM6805/CM6806 CM6903, Bleed Resistor Not
Required Negative Charge Pump Not Required for
the PFC section
PFC Section
114
Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Dlt50 needs Slope
Compensation
CM6805, CM6806 and CM6903
IAC enhances the THD during light load and high
line
115
Input Current Shaping Technique PFC with Leading
Edge Modulation Voltage Loop
CM6805, CM6806 and CM6903
or CM6805 Family
CM6800
For CM6800 family, ?VEAO6V-0.625V5.375V and
For CM6805, CM6806 and CM6903,
?VEAO(6V-0.625V)/41.34V
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Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Trailing Edge
Modulation PWM

• CM6805/CM6806 CM6903 PWM Control
• 1.5V Precision Current CMP
• 10 ms Digital Soft Start

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Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation Trailing Edge
Modulation PWM
PWM Section
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Input Current Shaping Technique (ICST) PFC with
Leading Edge Modulation
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Design High Density AC Adapter
8 Pin 12V Secondary Fly Back Smart Driver, CM6201
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Design High Density AC Adapter
8 Pin 12V Secondary Fly Back Smart Driver, CM6201

• Pin to pin compatible with STSR30
• Supply voltage range 7 to 13.2V
• Feed-Forward Peak Detect for wide input range
• CCM or DCM Fly-back operation
• Operating Frequency up to 750 KHz
• Automatic turn off for duty cycle less than 12.5
• Smart turn off (240nS)
• Output driver 15 Ohms sourcing and 6 Ohms
  sinking capability

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24-hour Engineering Supports
Input Current Shaping Technique PFC with Leading
Edge Modulation

• Champion Design Center
• www.champion-micro.com
• Design Excel Spread Sheets
• PWM design for Flyback Converter Section
• CM6805, CM6806, CM6903 Design Tool

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PWM design for Flyback Converter Section
Input Current Shaping Technique PFC with Leading
Edge Modulation
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CM6805 CM6806 CM6903 Design Tool
Input Current Shaping Technique PFC with Leading
Edge Modulation
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Summary High Density AC Adapter Design
Input Current Shaping Technique PFC with Leading
Edge Modulation

• without additional cost
• PFC Efficiency95.5 without additional cost
• 2 Level Boost Follower (200V and 380V)
• Use LETE, CM6805, CM6806 and CM6903 family
• FlyBack Efficiency87.5 (without SR)
• FlyBack Efficiency90 (with SR, CM6201)
• Total Efficiency from 83.56 to 86