CM6800T [CHAMP]
EPA/85 PFCPWM COMBO CONTROLLER;
| 型号： | CM6800T |
| 厂家： | 
CHAMPION MICROELECTRONIC CORP. |
| 描述： | EPA/85 PFCPWM COMBO CONTROLLER 功率因数校正 |
| 文件： | 总27页 (文件大小：852K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
GENERAL DESCRIPTION
FEATURES
CM6800T is a turbo-speed PFC and a Green PWM controller.
It is designed to further increase power supply efficiency while
using the relatively lower 380V Bulk Capacitor value.
Switching to CM6800T from your existing CM6800 family
boards can gain the following advanced performances:
Patents Pending
Pin to pin compatible with CM6802 family, CM6800
family, and ML4800 family
23V Bi-CMOS process
1.) Hold Up time can be increased ~ 30% from the
existing 6800 power supply
2.) Turbo Speed PFC may reduce 420 Bulk Capacitor
size
3.) 420V bulk capacitor value may be reduced and PFC
Boost Capacitor ripple current can be reduced
4.) No Load Consumption can be reduced 290mW at
270VAC
5.) Better Power Factor and Better THD
6.) Clean Digital PFC Brown Out
7.) PWM transformer size can be smaller
8.) Superior Surge Noise Immunity
9.) To design 12V, 5V, and 3.3V output filters can be easy
10.) The stress over the entire external power device is
reduced and EMI noise maybe reduced; PFC inductor
core might be reduced
Designed for EPA/85+ efficiency
Digitized Exactly 50% Maximum PWM Duty Cycle
All high voltage resistors can be greater than 4.7 Mega
ohm (4.7 Mega to 8 Mega ohm) to improve the no load
consumption
Rail to rail CMOS Drivers with on, 60 ohm and off, 30
ohm for both PFC and PWM with two 17V zeners
Fast Start-UP Circuit without extra bleed resistor to aid
VCC reaches 13V sooner
Low start-up current (55uA typ.)
Low operating current (2.5mA typ.)
16.5V VCC shunt regulator
11.) Monotonic Output design is easy
12.) And more… Of course, the cost can be reduced
Leading Edge Blanking for both PFC and PWM
fRTCT = 4*fpfc =4*fpwm for CM6800T
CM6800T is pin to pin compatible with CM6800 family.
Beside all the goodies in the CM6800, it is designed to meet
the EPA/85+ regulation. With the proper design, its efficiency
of power supply can easily approach 85%.
To start evaluating CM6800T from the exiting CM6800,
CM6800A, or ML4800 board, 6 things need to be taken care
before doing the fine tune:
Dynamic Soft PFC to ease the stress of the Power
Device and Ease the EMI filter design
Clean Digital PFC Brown Out and PWM Brown Out
Adjustable Long Delay Time for Line Sagging
(Up to 2 Second)
Turbo Speed PFC may reduce 420 Bulk Capacitor size
1.) Change RAC resistor (on pin 2, IAC) from the old
value to a higher resistor value between 4.7 Mega
ohm to 8 Mega ohm. Start with 6 Mega ohm for RAC
first.
2.) Change RTCT pin (pin 7) from the existing value to
RT=5.88K ohm and CT=1000pF to have fpfc=68Khz,
fpwm=68Khz, frtct=272Khz for CM6800T
Internally synchronized leading edge PFC and trailing
edge PWM in one IC to Reduces ripple current in the
420V storage capacitor between the PFC and PWM
sections
Better Power Factor and Better THD
Average current, continuous or discontinuous boost
leading edge PFC
3.) Adjust all high voltage resistor around 5 mega ohm or
higher.
4.) VRMS pin(pin 4) needs to be 1.14V at VIN=80VAC for
universal input application from line input from 80VAC
to 270VAC.
5.) At full load, the average Veao needs to around 4.5V
and the ripple on the Veao needs to be less than
250mV when the load triggers the light load
comparator.
6.) Soft Start pin (pin 5), the soft start current has been
reduced from CM6800’s 20uA to CM6800T’s
10uA.Soft Start capacitor can be reduced to 1/2 from
your original CM6800 capacitor.
PWM configurable for current mode or feed-forward
voltage mode operation
Current fed Gain Modulator for improved noise
immunity
Gain Modulator is a constant maximum power limiter
Precision Current Limit, over-voltage protection, UVLO,
soft start, and Reference OK
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
1
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
APPLICATIONS
PIN CONFIGURATION
EPA/85+ related Power Supply
Desktop PC Power Supply
Internet Server Power Supply
LCD Power Supply
SOP-16 (S16) / PDIP-16 (P16)
16
5
4
2
1
0
IEAO
1
2
3
4
5
6
7
8
VEAO
VFB
IAC
PDP Power Supply
VREF
ISENSE
IPC Power Supply
UPS
VCC
VRMS
SS
Battery Charger
PFC OUT
DC Motor Power Supply
Monitor Power Supply
Telecom System Power Supply
Distributed Power
VDC
PWM O
RAMP1
RAMP2
ND
DC ILIMIT
PIN DESCRIPTION
Oting Voltage
Pin No.
Symbol
Dscrptio
Min
Typ.
Max.
Unit
PFC transcductnce curent rroamplifieoutpt
I
1
0
VREF
V
(Gmi).
has funcons
1. PC gin mdulor rfernce iput.
2. Tpicl RArestor is out Mega ohm to sense
the lie.
IAC
2
0
100
uA
PFC Cuent ens: foboth Gain Modulator and PFC
ILIMT cmpartor.
ISENSE
3
4
-1.3
0
0.7
8
V
V
Line Inpt Sense pin and also, it is the brown out sense
pin
VRMS
oft start capacitor pin; it is pulled down by 70K ohm
internal resistor when DCILIMIT reach 1V; the power is
limited during the PWM Brown out.
5
S
0
VCC
V
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
2
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
6
7
VDC
0
10
4
V
V
DC to DC PWM voltage feedback input.
RAMP1
(RTCT)
RAMP 2
0.8
Oscillator timing node; timing set by RT and CT
In current mode, this pin functions as the current
sense input; when in voltage mode, it is the
feed-forward sense input from PFC output 380V (feed
forward ramp).
8
0
VDCm-1.
V
(PWM
RAMP)
9
DC ILIMIT
GND
1
PWM current limit comparator input
Ground
10
11
12
13
PWM OUT
PFC OUT
VCC
VCC
VC
18
V
V
V
PWM driver output
PFC driver output
0
5
7.5
2.5
Positive supply or CM6800T
Maximum 3.5mA buffereout or the ntenal 75V
reference wheC=1V
14
VREF
V
15
16
VFB
0
0
3
6
V
V
PFC traconuctace voltageror amplifieinpu
PFC anconuctace voltage eror amplifer output
(Gm)
VAO
ORDERING INFORMATION
Part Numbr
Temperature Range
-40℃ to 125℃
-40℃ to 125℃
-40℃ to 125℃
Package
16-Pin PDIP (P16)
CM6800TIP*
CM6800TS*
16-Pin Narrow SOP (S16)
16-Pin Narrow SOP (S16)
CM6800TXSTR*
*Note: X : Sfor Halogen Free and PB Free Product
TR : Package is Typing Reel
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
3
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
Simplified Block Diagram (CM6800T)
16
1
13
VCC
VEAO
IEAO
PFC OVP
+
VFB
.
GMv
+
-
-
16.5V
Zener
2.75V
.
Rmul
VREF
14
GMi
7.5
+
-
2.5V
PFC CMP
.
+
RFEENC
PFC Tri-Fault
VFB
-
+
15
0.5V
VFB
GAIN
MODULATOR
-
S
Q
Q
VCC
Rmul
PFC ILIMIT
R
IAC
PF
+
-1.0V
ISENSE
2
4
-
PFC RAMP
PFC OUT
12
S
Q
Q
VRMS
Green PFC
R
+
ISENSE
RAMP1
0.3V
VEAO
17V
ZENER
3
7
NPFC
-
PFC
PFCCLK
.
.
2K
RAMP2
PWMCLK
8
SW SPST
Green PWM
VC
M
NPFC
+
-
1.8V
VDC
VCC
S
S
R
WM OUT
6
5
-
11
10uA
17V
ZENER
VFB
70K
SS
2.36
38V-OK
UVLO
0V
VC
DC ILIMIT
GND
9
DC ILIIT
10
ABSLTE MAXIUM RATINGS
Absolue Maxmum rs arthosvales beynd whh te dece could be permanently damaged.
Parameter
VCC
Min.
Max.
18
Units
V
IEAO
ISENSVoltage
PFC OUT
PWMOUT
Voltge on Any Oher Pin
0
-5
VREF+0.3
0.7
VCC + 0.3
VCC + 0.3
VCC + 0.3
3.5
1
0.5
0.5
1.5
V
V
V
V
GND – 0.3
GND – 0.3
GND – 0.3
V
mA
mA
A
A
μJ
℃
℃
℃
℃
IREF
IAC Iput Current
PeaPFC OUCrrent, Souce or Sink
PeaPWM OT CurrenSorce or Sink
PFC OUT, PWM OT nergy Per Cycle
Juncon Temerat
150
150
125
260
Storae Temerature Range
Operng mperature Range
Lead rature (Soldering, 10 sec)
-65
-40
ThermaResistance (θJA)
Plastic DIP
Plastic SOIC
80
105
℃/W
℃/W
800
mW
Power Dissipation (PD) TA<50℃
ESD Capability, HBM Model
ESD Capability, CDM Model
5.5
KV
V
1250
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
4
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
ELECTRICAL CHARACTERISTICS:
Unless otherwise stated, these specifications apply Vcc=+14V, RT = 5.88 kΩ, CT = 1000pF, TA=Operating Temperature
Range (Note 1)
Symbol
Parameter
Test Conditions
CM600
Ty.
Unit
Min.
Mx.
Clean Digital PFC Brown Out
VRMS Threshold High
VRMS Threshold Low
Hysteresis
Room Temperature=25℃
1.70
0.8
70
1.78
1.03
86
08
60
V
V
Room Temperature=25℃
mV
Voltage Error Amplifier (gmv
)
Input Voltage Range
Transconductance
Feedback Reference Voltage
Input Bias Current
3
V
μmho
VNONINV = V, VEAO = 335V @ T25℃
5
4
2.52
-0.05
6.0
0.1
-40
3
60
2.
-1.0
5.8
2.58
V
μA
Note 2
OHigh Voltage
utput ow Vtae
Sink Curren
V
0.4
-28
7
V
μA
OvedrivVoge = 100mV @ T=25℃
Ovedrive oltage = 100mV @ T=25℃
Guaranteed by design
-60
0.9
30
μA
Source Curent
Open Loop Gain
40
dB
dB
Power Sppy RejctioRatio
11V < VCC < 16.5V
60
75
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
5
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
ELECTRICAL CHARACTERISTICS:
(Conti.) Unless otherwise stated, these specifications apply Vcc=+14V, RT = 5.88 kΩ, CT 1000pF,
TA=Operating Temperature Range (Note 1)
CM80T
Symbol
Parameter
Test Conditions
Unit
Min.
Typ.
Max
Current Error Amplifier (gmi)
Input Voltage Range (Isense pin)
-1.
50
0.7
5
V
μmho
VNONINV = VINV, IEAO = 1.5V @ T=25
Transconductance
Input Offset Voltage
Output High Voltage
Output Low Voltage
Sink Current
7
VEAO=0V, IC is open
-1
8
mV
V
.4
.1
34
77
04
-28
V
μA
SESE = -0.5, IEO = 1.5@ T=25℃
ISENSE = V, IEAO = 4.0V @ =2℃
DC Gai
-40
2
30
60
μA
Source Current
32
40
75
37
Open Loop Gain
dB
dB
Power Supply Rejection Ratio
1< CC < 16.
PFC OVP Compor
ThshoVolta
Hsteres
2.60
130
2.75
0.26
2.85
220
V
mV
PFC Green Pwer DetecCompaator
eao Threshold Voage
0.14
2.70
0.4
V
Tri-Fault Dect
ault Detect HIGH
2.85
2
3.0
4
V
ms
V
ime to FauDetet HGH
VFB=VFAULT DETECT LOW to
VFB=OPEN, 470pF from VFB to GND
ault Deect L
PFC ILIMIT Coparaor
Thold Voltage
0.1
0.28
0.4
-1.35
300
-1.25
450
-1.15
V
(PFCILIMIT– Gain Modulator
Output)
mV
ns
Delay to Output (Note 4)
Overdrive Voltage = -100mV
700
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
6
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
ELECTRICAL CHARACTERISTICS:
(Conti.) Unless otherwise stated, these specifications apply Vcc=+14V, RT = 5.88 kΩ, CT = 1000pF,
TA=Operating Temperature Range (Note 1)
CM6800T
Symbol
Parameter
Test Conditions
Unit
Min.
Typ.
Max.
DC ILIMIT Comparator
Threshold Voltage
0.92
10
0
V
Delay to Output (Note 4)
DC to DC PWM Brown Out Comparator
OK Threshold Voltage
Overdrive Voltage = 100mV
70
ns
2.1
23
2.5
V
Hysteresis
88
90
000
mV
GAIN Modulator
IAC = 20μA, VRM=1.125, VFB = 25V @
T=25℃ SS<VREF
Gain1 (Note 3)
Gain2 (Note )3
Gain3 (Note 3)
Gain4 (Note 3)
4.4
4
55
6.6
6
IAC = 20 μ A, VRMS = .455V, VFB
2.37V @ T=25℃ SSEF
=
IAC 20μA, VRM=2.1V, FB 2.35V @
T=5℃ SSEF
12
0.
15
1.05
1.8
1.3
IAC = 20μAVRS = 3.44VVB = 2375V
@ 25℃ SS<REF
IA= 0μA
Bandwidth (Note 4)
1
MHz
V
I
AC = 50μAVRMS = 125VVF= 2V
Output oltae = Rmul *
0.74
64
0.8
0.86
72
(ISEN-IOFFST
)
SSVRF
Oscillator (Measring fpfc)
RT 5.88 kΩT = 1000pF, TA = 25℃
Initiafpfc Accuracy 1
68
kHz
IAC=0u
Voltge Stability
11V < VCC < 16.5V
2
2
%
%
Temerature Staility
TotaVariatin
Line, Temp
60
75
kHz
V
Ramp y to Peak Voltage
PFC Dead Time (Note 4)
CT Discharge Current
VEAO=6V and IAC=20uA
2.5
11
550
10
950
12
ns
VRAMP2 = 0V, VRAMP1 = 2.5V
mA
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
7
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
ELECTRICAL CHARACTERISTICS (Conti.) Unless otherwise stated, these specifications apply
Vcc=+14V, RT = 5.88 kΩ, CT = 1000pF, TA=Operating Temperature Range (Note 1)
C680T
Symbol Parameter
Reference
Test Conditions
Unit
Min.
Typ
Ma.
TA = -45℃~85℃, I(VREF) = 0~3.5mA
11V < VCC < 16.5V@ T=25℃
Output Voltage
7.3
7.
3
7.
5
V
Line Regulation
Load Regulation
mV
VCC=10.5V,0mA < I(VREF) < mA;
@ T=25℃
25
5
50
mV
mV
VCC=14V,0mA < I(VREF) 3.5mA;
TA = -40℃~85℃
25
Temperature Stability
Total Variation
0.4
%
V
Line, Load, Temp
73
77
5
TJ = 125℃, 1000HRs
Long Term Stability
mV
PFC
Minimum Duty Cycle
Maximum Duty Cycle
IEAO > 4.5V
0
%
%
VIEAO < 1.2V
93
95
13
IOUT -20mA @ T=℃
18
18
1
ohm
IOUT -100@ T25℃
IOUT 10m, C = 9V @ T=25℃
IOUT 20mA @ T=5℃
Output Low Rdson
ohm
V
0.5
24
30
40
ohm
ohm
ns
Output High Rdson
I10mA @ T25℃
L 00F @ =2℃
Rise/Fall Time (Note 4)
50
13
PWM
Duty Cycle Range
Output Low Rdson
0-49.5
0-50
18
18
1
%
ohm
ohm
V
IOUT -2A @ T=5℃
IOUT -10mA @ T25℃
IOUT 10mA, VC = 9V
IOUT 20mA @ T=5℃
IOUT 10mA @ T25℃
CL = 00
0.5
26.5
40
40
ohm
ohm
ns
Oput HigRdso
Ris/Fali(Nte 4)
50
@ T25℃
PWM CmpaatoLeveSht
1.6
1.8
2
V
Soft Strt
Supply
μA
μA
m Temperature=25℃
Soft Strt Curent
7
10
3
12
6
Soft Strt Discharge Curen
ms=0.926V, Soft Start=8V
0.5
μA
mA
VCC = 12V, CL = 0 @ T=25℃
Start-Up Currnt
Operang Cuen
50
65
14V, CL = 0
CM6800T
CM6800T
CM6800T
2.5
3.5
13.65
10.25
3.1
Turnon Underoltage Lockout Threshold
Turnoff Unervltage Locout Threshold
Turnoff UnervltagLockout Hysteresis
Shunt egulatr (Vener)
12.35
9.75
2.8
12.85
V
V
2.95
17
V
Zeer Tshold Voltage
Apply VCC with Iop=20mA
16.15
17.85
V
Note 1: mits re guaranteed by 100% testing, sampling, or correlation with worst-case test conditions.
Note 2: s all bias currents to other circuits connected to the VFB pin.
Note 3: G~ K x 5.3V; K = (ISENSE – IOFFSET) x [IAC (VEAO – 0.7)]-1; VEAOMAX = 6V
Note 4: Guaranteed by design, not 100% production test.
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
8
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
TYPICAL PERFORMANCE CHARACTERISTIC:
PFC Soft Diagram :
Dynamic Soft PFC Performance @ Vin=110 Vac
Ch1 is 380V bulk cap voltage which is 100V/div.
Ch3 is Input Line Current which is 1A/div.
Input Line Voltage (110 Vac) was turned off for 40mS before reaching PWM Brownout which is 209Vdc. When the bulk cap voltage goes below
209V, the system will reset the PWM soft start. The result of the CM6800T Input Line Current has a clean Off and softly On even the system
does not reset PWM soft-start.
Dynamic Soft PFC Performance @ Vin=220 Vac
Ch1 is 380V bulk cap voltage which is 100V/div.
Ch3 is Input Line Current which is 1A/div.
Input Line Voltage (220 Vac) was turned off for 40mS before reaching PWM Brownout which is 209Vdc when Bulk cap voltage drops below
209V. When the bulk cap voltage goes below 209V, the system will reset the PWM soft start. The result of the CM6800T Input Line Current has
a clean Off and softly On even the system does not reset itself. The first peak current at the beginning of the On time is the inrush current.
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
9
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
Turn on Timing :
Output 50% and 100% load turn on waveform at 110Vac
Ch1 is 380V bulk cap voltage which is 100V/dv.
Ch2 is VCC,Ch3 is SS(soft start pin),CH4 is V2V).
Output 10% and 20% load turn on waveform at 230Vac
Output 50% nd 00% loatun on wveforat 230Vac
Ch1 is 380V ulk cavoltaich 100/div
Ch2 is VCCCh3 is SS(sofstarpin)CH4 iVo(2V)
Ch1 is 380V bulk cap voltage which is 100V/div.
Ch2 is VCC,Ch3 is SS(soft start pin),CH4 is Vo(12V)
Dynamic load:
Ch1 is 380V bulk cap voltage which is 100V/div.
Ch2 is VCC,Ch3 is SS(soft start pin),CH4 is Vo(12V)
Ch1 is 380V bulk cap voltage which is 100V/div.
Ch2 is VCC,Ch3 is SS(soft start pin),CH4 is Vo(12V)
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
10
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
AC power cycling :
90VAC turn on 500ms turn off 100ms at 10%LOAD
Ch2 is AC input voltage which is 100V/div.
Ch3 s PFstae Msfet Din crre(zoom In
Ch3 is PFC stage Mosfet drain current, CH4 is Vo(V
90VAC turn n 500ms turn of100ms at 00%LOAD
Ch2 is AC input voltage which i10V/div.
Ch3 is PFC stage Mosfet Drain current(zoom In)
Ch3 is FC stage Most drain urrnt, CHis V(12V)
90VAC turn on 500ms turn off 10ms at 10%LOAD
Ch2 is AC input voltage which is 100V/div.
Ch3 is PFC stage Mosfet Drain current (zoom In)
Ch3 is PFC stage Mosfet drain current, CH4 is Vo (12V)
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
11
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
90VAC turn on 500ms turn off 10ms at 100%LOAD
Ch2 is AC input voltage which is 100V/div.
h3 is PFC tage Most Dran curenzoon)
Ch3 is PFC stage Mosfet drain current, CH4 is (2V)
230VAC trn on 500ms urn off 100ms at 10%LOD
Ch2 is AC input voltae which s 10V/di
Ch3 is PFC stage Mosfet Drain current (zoom In)
Ch3 is PFC stage Mofet draicuent, CH4 is Vo (12V)
23VAC turn on 500ms turn off 100ms at 100%LOAD
Ch2 is AC input voltage which is 100V/div.
Ch3 is PFC stage Mosfet Drain current (zoom In)
Ch3 is PFC stage Mosfet drain current, CH4 is Vo (12V)
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
12
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
230VAC turn on 500ms turn off 10ms at 10%LOAD
Ch2 is AC input voltage which is 100V/d
Ch3 is PFC tagMsfet racurent (zoom In)
Ch3 is PFC stage Mosfet drain current, H4 is Vo (12V)
230VAC tuon 50ms tuoff 1ms at 0%LOAD
Ch2 is AC nput voltge w100V/div.
Ch3 is PFC stage Mosfet Drain current (zoom In)
Ch3 is PFstage Mosfet dcurrent, CH4 is Vo (12V)
2010/08/03 Rev. 1.2
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CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
Power Factor Correction
Getting Start:
Power factor correction makes a nonlinear load look like a
resistive load to the AC line. For a resistor, the current drawn
from the line is in phase with and proportional to the line
voltage, so the power factor is unity (one). A common class of
nonlinear load is the input of most power supplies, which use a
bridge rectifier and capacitive input filter fed from the line. The
To start evaluating CM6800T from the exiting CM6800 or
ML4800 board, 6 things need to be taken care before doing
the fine tune:
1.) Change RAC resistor (on pin 2, IAC) from the old value to
a higher resistor value between 4.7 Mega ohms to 8 Mega peak-charging effect, which occurs on the input filter capacitor
in these supplies, causes brief high-amplitude pulses of current
to flow from the power line, rather than a sinusoidal current in
phase with the line voltage. Such supplies present a power
factor to the line of less than one (i.e. they cause significant
current harmonics of the power line frequency to appear at
their input). If the input current drawn by such a supply (or any
other nonlinear load) can be made to follow the input voltage in
instantaneous amplitude, it will appear resistive to the AC line
and a unity power factor will be achieved.
ohms.
2.) Change RTCT pin (pin 7) from the existing value to
RT=5.88K ohm and CT=1000pF to have fpfc=68 Khz,
fpwm=68Khz, fRTCT=272Khz for CM6800T.
3.) Adjust all high voltage resistor around 5 mega ohm or
higher.
4.) VRMS pin (pin 4) needs to be 1.14V at VIN=80Vac and to
be 1.21V at VIN=80VAC for universal input application
from line input from 80VAC to 270VAC.
5.) At full load, the average Veao needs to around 4.5V and
the ripple on the Veao needs to be less than 250mV when
the light load comparator are triggerred.
To hold the input current draw of a device drawing power
from the AC line in phase with and proportional to the input
voltage, a way must be found to prevent that device from
loading the line except in proportion to the instantaneous line
voltage. The PFC section of the CM6800T uses a boost-mode
DC-DC converter to accomplish this. The input to the converter
is the full wave rectified AC line voltage. No bulk filtering is
applied following the bridge rectifier, so the input voltage to the
boost converter ranges (at twice line frequency) from zero volts
to the peak value of the AC input and back to zero. By forcing
the boost converter to meet two simultaneous conditions, it
is possible to ensure that the current drawn from the power line
is proportional to the input line voltage. One of these conditions
is that the output voltage of the boost converter must be set
higher than the peak value of the line voltage. A commonly
6.) Soft Start pin (pin 5), the soft start current has been
reduced from CM6800’s 20uA to CM6800T’s 10uA.Soft
Start capacitor can be reduced to 1/2 from your original
CM6800 capacitor.
Functional Description
CM6800T is designed for high efficient power supply for both
full load and light load. It is a popular EPA/85+ PFC-PWM
power supply controller.
used value is 385VDC, to allow for a high line of 270VACrms
.
The other condition is that the current drawn from the line at
any given instant must be proportional to the line voltage.
Establishing a suitable voltage control loop for the converter,
which in turn drives a current error amplifier and switching
output driver satisfies the first of these requirements. The
second requirement is met by using the rectified AC line
voltage to modulate the output of the voltage control loop. Such
modulation causes the current error amplifier to command a
power stage current that varies directly with the input voltage.
In order to prevent ripple, which will necessarily appear at the
output of boost circuit (typically about 10VAC on a 385V DC
level); from introducing distortion back through the voltage
error amplifier, the bandwidth of the voltage loop is deliberately
kept low. A final refinement is to adjust the overall gain of the
PFC such to be proportional to 1/(Vin x Vin), which linearizes
the transfer function of the system as the AC input to voltage
varies.
The CM6800T consists of an average current controlled
continuous/discontinuous boost Power Factor Correction
(PFC) front end and a synchronized Pulse Width Modulator
(PWM) back end. The PWM can be used in either current or
voltage mode. In voltage mode, feed-forward from the PFC
output bus can be used to improve the PWM’s line regulation.
In either mode, the PWM stage uses conventional trailing edge
duty cycle modulation, while the PFC uses leading edge
modulation. This patented leading/trailing edge modulation
technique results in a higher usable PFC error amplifier
bandwidth, and can significantly reduce the size of the PFC
DC buss capacitor.
The synchronized of the PWM with the PFC simplifies the
PWM compensation due to the controlled ripple on the PFC
output capacitor (the PWM input capacitor). In addition to
power factor correction, a number of protection features have
been built into the CM6800T. These include soft-start, PFC
over-voltage protection, peak current limiting, brownout
protection, duty cycle limiting, and under-voltage lockout.
Since the boost converter topology in the CM6800T PFC is
of the current-averaging type, no slope compensation is
required.
More exactly, the output current of the gain modulator is given
by:
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Dynamic Soft PFC (patent pending)
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
Gain=Imul/Iac
Besides all the goodies from CM6800A, Dynamic Soft PFC
is the main feature of CM6800T. Dynamic Soft PFC is to
improve the efficiency, to reduce power device stress, to ease
EMI, and to ease the monotonic output design while it has the
more protection such as the short circuit with power-foldback
protection. Its unique sequential control maximizes the
performance and the protections among steady state, transient
and the power on/off conditions.
K=Gain/(VEAO-0.7V)
I
mul = K x (VEAO – 0.7V) x IAC
Where K is in units of [V-1]
Note that the output current of the gain modulator is limited
around 100 μA and the maximum output voltage of the gain
modulator is limited to 100uA x 7.75K≒0.8V. This 0.8V also
PFC Section:
Gain Modulator
will determine the maximum input power.
Figure 1 shows a block diagram of the PFC section of the
CM6800T. The gain modulator is the heart of the PFC, as it is
this circuit block which controls the response of the current
loop to line voltage waveform and frequency, rms line voltage,
and PFC output voltages. There are three inputs to the gain
modulator. These are:
However, IGAINMOD cannot be measured directly from ISENSE
.
ISENSE = IGAINMOD-IOFFSET and IOFFSET can only be measured
when VEAO is less than 0.5V and IGAINMOD is 0A. Typical
IOFFSET is around 25uA.
IAC=20uA, Veao=6V
1. A current representing the instantaneous input voltage
(amplitude and wave-shape) to the PFC. The rectified AC
input sine wave is converted to a proportional current via a
resistor and is then fed into the gain modulator at IAC
.
Sampling current in this way minimizes ground noise, as is
required in high power switching power conversion
environments. The gain modulator responds linearly to this
current.
2. A voltage proportional to the long-term RMS AC line voltage,
derived from the rectified line voltage after scaling and
filtering. This signal is presented to the gain modulator at
VRMS. The gain modulator’s output is inversely proportional
to VRMS2. The relationship between VRMS and gain is
illustrated in the Typical Performance Characteristics of this
page.
3. The output of the voltage error amplifier, VEAO. The gain
modulator responds linearly to variations in this voltage.
Gain vs. VRMS (pin4)
The output of the gain modulator is a current signal, in the
form of a full wave rectified sinusoid at twice the line
frequency. This current is applied to the virtual-ground
(negative) input of the current error amplifier. In this way the
gain modulator forms the reference for the current error loop,
and ultimately controls the instantaneous current draw of the
PFC from the power line. The general formula of the output of
the gain modulator is:
When VRMS below 1V, the PFC is shut off. Designer needs
to design 80VAC with VRMS average voltage= 1.14V.
ISENSE − IOFFSET IMUL
Gain =
=
IAC
IAC
Selecting RAC for IAC pin
I
AC× (VEAO - 0.7V)
x constant
IAC pin is the input of the gain modulator. IAC also is a
current mirror input and it requires current input. By selecting a
proper resistor RAC, it will provide a good sine wave current
derived from the line voltage and it also helps program the
maximum input power and minimum input line voltage.
Imul
=
(1)
2
V
RMS
RAC=Vin min peak x 53.03K. For example, if the minimum line
voltage is 80VAC, the RAC=80 x 1.414 x 53.03K = 6 Mega ohm.
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EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
Vrms Description:
Cycle-By-Cycle Current Limiter and
Selecting RSENSE
VRMS is the one of the input for PFC Gain Modulator. Besides
it is the input of the Gain Modulator, it also serves for Clean
Digital PFC Brown Out function:
The ISENSE pin, as well as being a part of the current
feedback loop, is a direct input to the cycle-by-cycle current
limiter for the PFC section. Should e input voltage at this pin
ever be more negative than –1thouput of the FC will be
disabled until the protection fliplop is reset by the clock pulse
at the start of the next PFC powr cycle.
RS is the sensing resistor of te PFC sconvrter. During
the steady stateline input cuent x SENS= Iul x 7.75K.
Since the maximm output voltage thgaimoulator is Imul
max x 7.75K≒ .8V during the seadstae, RSENSE x line
input currenwill be limibelw 8V as wll. When VEAO
reaches maxmum VEAhich is 6V, Iense careach 0.8V.
At 100% lod, VEAO shold e roud 4.5V and ISENSE
average pek is 0.6. It will prode the optmal dynamic
response + race f the omonnts
VRMS is used to detect the AC Brown Out (Also, we can call it
Clean Digital PFC brown out.). When VRMS is less than 1.0 V
+/-3%, PFCOUT will be turned off and VEAO will be softly
discharged. When VRMS is greater than 1.75V +/-3%,
PFCOUT is enabled and VEAO is released.
Clean Digital PFC Brown Out
Clean Digital PFC Brown Out provides a clean cut off when
AC input is much lower than regular AC input voltage such as
70Vac.
Inside of Clean Digital PFC Brown Out, there is a
comparator monitors the Vrms (pin 4) voltage. Clean Digital
PFC Brown Out inhibits the PFC, and Veao (PFC error
amplifier output) is pulled down when the Vrms is lower than
off threshold, 1.0V (The off Vin voltage usually correponds to
70Vac). When the Vrms voltage reaches 1.75V (ThOn Vin
voltage usually corresponds to 86.6V and when Vin = 80Vac,
Vrms = 1.14V), PFC is on.
There, to chose RSENwe use the ollowiequation:
RESE RPaasitic 0.6V Vipeak / (x Lne Inpt power)
or eampe, if he inimm iput volte is 80VAC, and the
mximum input ms poweis 200Watt, RSENE + RParasitic
(06V x 80V x 1.14/ (2 20) = 0.169 ohmThe designer
neds tcosidethpaitic resistance anthe margin of
thpower spplandymic response. Aume RParasitic
0.3Ohm, RENSE 0Ohm.
=
Before PFC is turned on, Vrms (pin epresents the pa
voltage of the AC input. Before PFC is turned off, Vrs (pn 4)
represents the Vrms voltage of the AC nput.
=
Current Error Amplifier, IEO
PFC OVP
The current error amplifier’utpucorolthe FC duty
cycle to p the average uthrough he boost dutor a
linear cn of the line vageAt he iveing inut o the
curreerroamplifithe tput currnt othgain odlator
is sumed wth a nt wich resultfrom a egatie voag
beinimpressed pon he SENSE pin. The egtive oltag
ISENE represents the um of all currnts lowng ithe PFC
circit, and is typcally eried from a currnt snsesistor in
sers with the ngative erminal othe inpubrirectifier.
In the CM680T, PFC OVP comparator serves to protect the
pwer ccuit from being subjected to excessive voltages if the
lod should suddenly change. A resistor divider from the high
votage DC output of the PFC is fed to VFB. When the voltage
on VFB exceeds ~ 2.75V, the PFC output driver is shut down.
The PWM section will continue to operate. The OVP
comparator has 250mV of hysteresis, and the PFC will not
restart until the voltage at VFB drops below ~ 2.55V. The VFB
power components and the CM6800T are within their safe
operating voltages, but not so low as to interfere with the boost
voltage regulation loop.
In igher poweappliatins, to curretransformers are
soetimes usedone tmnitor he IF of the boost diode. As
staed above, thinvertng nput othe current error amplifier is
a vrtual groundGiven thifact, and the arrangement of the
ducycle mduator plaries internal to the PFC, an increase
in ositive urrt frm te gain modulator will cause the
outut stagto crase its duty cycle until the voltage on
ISENE is adquategative to cancel this increased current.
Simarly, if he gain modulator’s output decreases, the output
duty ycle ill decrease, to achieve a less negative voltage on
the Iin.
The Current Loop Gain (S)
ΔV
ΔDOFF
ΔIEAO
ΔIEAO
ISENSE
=
≈
*
*
ΔDOFF
OUTDC *RS
ΔISENSE
V
* GMI * ZCI
S *L * 2.5V
ZCI: Compensation Net Work for the Current Loop
GMI: Transconductance of IEAO
VOUTDC: PFC Boost Output Voltage; typical designed value is
380V and we use the worst condition to calculate the ZCI
RSENSE: The Sensing Resistor of the Boost Converter
2.5V: The Amplitude of the PFC Leading Edge Modulation
Ramp(typical)
L: The Boost Inductor
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
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CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
Error Amplifier Compensation
The PWM loading of the PFC can be modeled as a negative
resistor; an increase in input voltage to the PWM causes a
decrease in the input current. This response dictates the
proper compensation of the two transconductance error
amplifiers. Figure 2 shows the types of compensation networks
most commonly used for the voltage and current error
amplifiers, along with their respective return points. The current
loop compensation is returned to VREF to produce a soft-start
characteristic on the PFC: as the reference voltage comes up
from zero volts, it creates a differentiated voltage on IEAO which
prevents the PFC from immediately demanding a full duty
cycle on its boost converter.
The gain vs. input voltage of the CM6800T’s voltage error
amplifier, VEAO has a specially shaped non-linearity such that
under steady-state operating conditions the transconductance
of the error amplifier, GMv is at a local minimum. Rapid
perturbation in line or load conditions will cause the input to the
voltage error amplifier (VFB) to
I
SENSE Filter, the RC filter between RSENSE and ISENSE
:
There are 2 purposes to add a filter at ISENSE pin:
1.) Protection: During start up or inrush current conditions, it
will have a large voltage cross Rs which is the sensing
resistor of the PFC boost converter. It requires the ISENSE
Filter to attenuate the energy.
PFC Voltage Loop
There are two major concerns when compensating the
voltage loop error amplifier, VEAO; stability and transient
response. Optimizing interaction between transient response
and stability requires that the error amplifier’s open-loop
crossover frequency should be 1/2 that of the line frequency,
or 23Hz for a 47Hz line (lowest anticipated international power
frequency).
2.) To reduce L, the Boost Inductor: The ISENSE Filter To
reduce L, the Boost Inductor: The ISENSE Filter also can
reduce the Boost Inductor value since the ISENSE Filter
behaves like an integrator before going ISENSE which is the
input of the current error amplifier, IEAO.
The ISENSE Filter is a RC filter. The resistor value of the ISENSE
Filter is between 100 ohm and 50 ohm because IOFFSET x the
resistor can generate an offset voltage of IEAO. By selecting
RFILTER equal to 50 ohm will keep the offset of the IEAO less
than 5mV. Usually, we design the pole of ISENSE Filter at
fpfc/6=8.33Khz, one sixth of the PFC switching frequency.
Therefore, the boost inductor can be reduced 6 times without
disturbing the stability. Therefore, the capacitor of the ISENSE
Filter, CFILTER, will be around 381nF.
deviate from its 2.5V (nominal) value. If this happens, the
transconductance of the voltage error amplifier, GMv will
increase significantly, as shown in the Typical Performance
Characteristics. This raises the gain-bandwidth product of the
voltage loop, resulting in a much more rapid voltage loop
response to such perturbations than would occur with a
conventional linear gain characteristics.
The Voltage Loop Gain (S)
ΔVOUT ΔVFB ΔVEAO
=
≈
*
*
ΔVEAO ΔVOUT ΔVFB
PIN*2.5V
*GM *ZCV
V
V
OUTDC2 *ΔVEAO*S*CDC
ZCV: Compensation Net Work for the Voltage Loop
GMv: Transconductance of VEAO
PIN: Average PFC Input Power
VOUTDC: PFC Boost Output Voltage; typical designed value is
380V.
CDC: PFC Boost Output Capacitor
PFC Current Loop
The current transcondutance amplifier, GMi, IEAO
compensation is similar to that of the voltage error amplifier,
VEAO with exception of the choice of crossover frequency.
The crossover frequency of thecurrent amplifier should be at
least 10 times that of the voltage amplifier, to prevent
interaction with the voltage loop. It should also be limited to
less than 1/6th that of the switching frequency, e.g. 8.33kHz for
a 50kHz switching frequency.
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CM6800T (Turbo-Speed PFC+Green PWM)
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EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
16
1
13
VCC
VEAO
IEAO
PFC OVP
+
VFB
.
GMv
+
-
16.5V
Zener
2.75V
.
Rmul
VREF
14
GMi
7.5V
-
+
-
2.5V
PFC CMP
.
+
REFERENCE
PFC Tri-Fault
VFB
15
-
+
0.5V
VFB
GAIN
-
S
Q
Q
VCC
Rmul
MODULATOR
PFC ILIMIT
R
IAC
2
MPPC
+
-1.0V
ISENSE
-
PFC RAMP
PFC OT
12
S
Q
Q
VRMS
4
3
Green PFC
R
+
0.3V
VEAO
ISENSE
17
ZEER
-
MNC
PFC
RAMP1
PFCCLK
7
.
Figure 1. PFC Section Block Diagram
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EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
Oscillator (RAMP1, or called RTCT)
In current-mode applications, the PWM ramp (RAMP2) is usually
derived directly from a current sensing resistor or current
transformer in the primary of the output stage, and is thereby
representative of the current flowing in the converter’s output
stage. DCILIMIT, which provides cycle-by-cycle current limiting, is
typically connected to RAMP2 in such applications. For
voltage-mode, operation or certain specialized applications,
RAMP2 can be connected to a separate RC timing network to
generate a voltage ramp against which VDC will be compared.
Under these conditions, the use of voltage feed-forward from the
PFC buss can assist in line regulation accuracy and response. As
in current mode operation, the DC ILIMIT input is used for output
stage over-current protection.
In CM6800T, fRTCT=4xfpwm=4xfpfc fRTCT=272Khz,
fpwm=68Khz and fpfc=68Khz, it provides the best
performance in the PC application.
The oscillator frequency, fRTCT is the similar formula in
CM6800:
1
fRTCT =
t
RAMP + tDEADTIME
The dead time of the oscillator is derived from the
following equation:
V
REF −1.25
REF − 3.75
tRAMP = CT x RT x In
V
No voltage error amplifier is included in the PWM stage of the
CM6800T, as this function is generally performed on the output
side of the PWM’s isolation boundary. To facilitate the design of
opto-coupler feedback circuitry, an offset has been built into the
PWM’s RAMP2 input which allows VDC to command a zero
percent duty cycle for input voltages below around 1.8V.
at VREF = 7.5V:
RAMP = CT x RT x 0.51
t
The dead time of the oscillator may be determined using:
2.5V
tDEADTIME
=
x CT = 686.8 x CT
3.64mA
PWM Current Limit (DCILIMIT)
The dead time is so small (tRAMP >> tDEADTIME ) that the
operating frequency can typically be approximately by:
The DC ILIMIT pin is a direct input to the cycle-by-cycle current
limiter for the PWM section. Should the input voltage at this pin
ever exceed 1V, the output flip-flop is reset by the clock pulse at
the start of the next PWM power cycle. Beside, the cycle-by-cycle
current, when the DC ILIMIT triggered the cycle-by-cycle current.
It will limit PWM duty cycle mode. Therefore, the power
dissipation will be reduced during the dead short condition.
When DCILIMIT pin is connected with RAMP2 pin, the
CM6800T’s PWM section becomes a current mode PWM
controller. Sometimes, network between DCILIMIT and RAMP2 is
a resistor divider so the DCILIMIT’s 1V threshold can be amplified
to 1.8V or higher for easy layout purpose.
1
fRTCT =
t
RAMP
Ct should be greater than 470pF.
Let us use 1000PF Solving for RT yields 5.88K. Selecting
standard components values, CT = 1000pF, and RT
=
5.88kΩ
The dead time of the oscillator determined two things:
1.) PFC minimum off time which is the dead time
PWM Brown Out (380V-OK Comparator)
2.) PWM skipping reference duty cycle: when the PWM
duty cycle is less than the dead time, the next cycle
will be skipped and it reduces no load consumption
in some applications.
The 380V-OK comparator monitors the DC output of the PFC
and inhibits the PWM if this voltage on VFB is less than its nominal
2.36V. Once this voltage reaches 2.36V, which corresponds to
the PFC output capacitor being charged to its rated boost voltage,
the soft-start begins. It is a hysteresis comparator and its lower
threshold is 1.35V.
PWM Section
Pulse Width Modulator
The PWM section of the CM6800T is straightforward, but
there are several points which should be noted. Foremost
among these is its inherent synchronization to the PFC
section of the device, from which it also derives its basic
timing. The PWM is capable of current-mode or
voltage-mode operation.
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EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
PWM Control (RAMP2)
When the PWM section is used in current mode, RAMP2 is
A filter network is recommended between VCC (pin 13) and
bootstrap winding. The resistor of the filter can be set as
following.
RFILTER x IVCC ~ 2V, IVCC = IOP + (QPFCFET + QPWMFET ) x fsw
IOP = 3mA (typ.)
generally used as the sampling point for
a voltage
representing the current on the primary of the PWM’s output
transformer, derived either by a current sensing resistor or a
current transformer. In voltage mode, it is the input for a ramp
voltage generated by a second set of timing components
(RRAMP2, CRAMP2),that will have a minimum value of zero volts
and should have a peak value of approximately 5V. In voltage
mode operation, feed-forward from the PFC output buss is an
excellent way to derive the timing ramp for the PWM stage.
EXAMPLE:
With a wanting voltage called, VBIAS ,of 18V, a VCC of 15V
and the CM6800T driving a total gate charge of 90nC at
100kHz (e.g. 1 IRF840 MOSFET and 2 IRF820 MOSFET), the
gate driver current required is:
Soft Start (SS)
Start-up of the PWM is controlled by the selection of the
external capacitor at SS. A current source of 10μA supplies
IGATEDRIVE = 100kHz x 90nC = 9mA
the charging current for the capacitor, and start-up of the
PWM begins at SS~1.8V. Start-up delay can be programmed
by the following equation:
V
BIAS − VCC
RBIAS
RBIAS
=
=
I
CC + I
G
18V −15V
5mA + 9mA
10μA
SS = tDELAY x
C
1.8V
Choose RBIAS = 214Ω
where CSS is the required soft start capacitance, and the tDEALY
is the desired start-up delay.
The CM6800T should be locally bypassed with a 1.0 μ F
ceramic capacitor. In most applications, an electrolytic
capacitor of between 47 μ F and 220 μ F is also required
across the part, both for filtering and as part of the start-up
bootstrap circuitry.
It is important that the time constant of the PWM soft-start
allow the PFC time to generate sufficient output power for the
PWM section. The PWM start-up delay should be at least
5ms.
Solving for the minimum value of CSS
:
Leading/Trailing Modulation
10μA
CSS = 5ms x
≒ 27nF
1.8V
Conventional Pulse Width Modulation (PWM) techniques
employ trailing edge modulation in which the switch will turn on
right after the trailing edge of the system clock. The error
amplifier output is then compared with the modulating ramp up.
The effective duty cycle of the trailing edge modulation is
determined during the ON time of the switch. Figure 4 shows a
typical trailing edge control scheme.
Caution should be exercised when using this minimum soft
start capacitance value because premature charging of the
SS capacitor and activation of the PWM section can result if
VFB is in the hysteresis band of the 380V-OK comparator at
start-up. The magnitude of VFB at start-up is related both to
line voltage and nominal PFC output voltage. Typically, a
0.05μF soft start capacitor will allow time for VFB and PFC
out to reach their nominal values prior to activation of the
PWM section at line voltages between 90Vrms and 265Vrms.
Generating VCC
After turning on CM6800T at 13V, the operating voltage can
vary from 10V to 17.9V. That’s the two ways to generate VCC.
One way is to use auxiliary power supply around 15V, and the
other way is to use bootstrap winding to self-bias CM6800T
system. The bootstrap winding can be either taped from PFC
boost choke or from the transformer of the DC to DC stage.
The ratio of winding transformer for the bootstrap should be
set between 18V and 15V.
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
20
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
In case of leading edge modulation, the switch is turned
OFF right at the leading edge of the system clock. When the
modulating ramp reaches the level of the error amplifier output
voltage, the switch will be turned ON. The effective duty-cyle
of the leading edge modulation is determined during OFF tme
of the switch.
Figure 5 shows a leading edge control sche
One of the advantages of this control tehnique is thait
required only one system clock. Switch 1(SW1) turns nd
switch 2 (SW2) turns on at the same instat to minihe
momentary “no-load” period, thus lowerig ripple volge
generated by the switching action. With sh ynhroned
switching, the ripple voltage of the first gis reducd.
Calculation and evaluation have showthathe 120Hz
component of tPFC’s output rippoltae cabredued
by as much a% using this mehd
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
21
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
APPLICATION CIRCUIT (Voltage Mode)
GBL408
4
L
+
-
1
FG
N
EMI Circuit
IN5406
IN5406
AC INLET
0.22 2W(s)
0.2 2W(s)
1uF/400V
GND
47
N54
3M1%
1M
1M
VCC
L 1
380VDC
B+
1
+
22uF/25V
0.1uf/25v
0.47UF
0.47uF
1M 1%
A/600V
13
3
S2795
3M 1%
VCC ISENSE
VEAO
243K
200K 1%
0.047uF
16
1N41
0.47uF
260
2
1
0.47uF/16V
IAC
1M 1%
41000pF
36.5K
15
6
+
VFB
Vrms
150uF/450V
30.1K
10K
20
12
VDC PFCOUT
R16
B
MPS7
4700pF
22K
10
1
C
IEAO
11
8
PWMOUT
N22
14
7
PWOUT
VREF RAMP2
470pF
470pF/250V
470
13K 1%
2N29
9
470pF
RP1 DCIlim
IS
2K 1%
14K 1%
D
0
SS
5
VREF
820pF
2200P
470pF
0.1uF
ISO1A
817C
0.04
+5
+12V
ISO1A
10.2K 1%
1000P
10
817C
A
L3
1K
380VDC
PARE)
+12V
PWM OUT
10
R5*
20N60
28TS
4.7K
0.1uF
+
1
RL-35
+
2200uF/16V
10K
220016V
0PF
1uF
20
GND
+5V
55Ts
BYV-26G
2200PF
L4
39.2K 1%
L1
30L30
EGP
S
R5*25
1
TL431
10PF
+
+
ER35
20N60
2200uF/6.3V
4.75K 1% 1/8W
2200uF/10V
0
EI10 PC
10
GND
1
PWM IS
0.2/2S)
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
22
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
For Line Sagging Delay Application Circuit (Voltage Mode)
GBL408
4
L
+
-
1
FG
N
EMI Circuit
IN5406
IN5406
AC INLET
0.22 2W(s)
0.2 2W(s)
1uF/400V
GND
47
N54
3M1%
1M
1M
VCC
L
380VDC
B+
1
+
22uF/25V
0.1uf/25v
0.47UF
0.47uF
1M 1%
A/600V
13
3
S2795
3M 1%
VCC ISENSE
VEAO
243K
200K 1%
0.047uF
16
1N41
0.47u
260
2
4
1
0.47uF/16V
IAC
1M 1%
1000pF
36.5K
15
6
+
VFB
Vrms
150uF/450V
30.1K
10K
20
12
VDC PFCOUT
R16
B
MPS7
4700pF
22K
10
1
C
IEAO
11
8
PWMOUT
N22
14
7
PWOUT
VREF RAMP2
470pF
470pF/250V
470
13K 1%
2N29
9
470pF
RP1 DCIlim
S
2K 1%
14K 1%
D
0
SS
5
VREF
820pF
10K
2200P
470pF
0.1uF
ISO1A
817C
IN4148
1u
+5
+12V
ISO1A
10.2K 1%
1000P
10
817C
L1A
L3
1K
380VDC
SPARE)
+12V
PWM OUT
R5*25
20N60
28T
4.7K
0.1uF
+
1
RL-35
+
2200uF/16V
10K
220016V
0PF
1uF
20
GND
+5V
55Ts
BYV-26
2200PF
L4
39.2K 1%
L
30L30
YGP
TS
R5*25
1
TL431
10PF
+
+
ER35
20N60
2200uF/6.3V
4.75K 1% 1/8W
2200uF/10V
10
EI10 P
10
GND
1
PWM IS
0.2/2S)
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
23
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
APPLICATION CIRCUIT (Current Mode)
GBL408
4
L
+
-
1
FG
N
EMI Circuit
IN5406
IN5406
AC INLET
0.22 2W(s)
0.2 2W(s)
1uF/400V
GND
47
N54
3M1%
1M
1M
VCC
L 1
B+
1
+
22uF/25V
0.1uf/25v
380VDC
0.47UF
A/600V
13
3
1M 1%
S2795
VCC ISENSE
VEAO
243K
200K 1%
3M 1%
1000pF
16
1N41
0.47uF
260
2
4
1
0.47uF/16V
0.047uF
IAC
1M 1%
36.5K
15
6
0.47uF
+
VFB
Vrms
150uF/450V
10K
20
12
VDC PFCOUT
R1
B
MPS7
4700pF
22K
1
10
V
2N222
IEAO
11
8
PWMOUT
14
7
VREF RAMP2
PWM OUT
470pF
470pF/250V
9
2N297
13K 1%
RP1 DCIlim
470pF
PS
2K 1%
14K 1%
D
0
SS
5
470
VREF
0.1uF
20
470pF
ISO1A
817C
0.047
+5
+12V
ISO1A
0.2K 1%
1000
10
817C
L3
1K
380VDC
PARE)
+12V
PWM OUT
10
R5*
20N60
28TS
4.7K
0.1uF
+
1
RL-35
+
2200uF/16V
10K
220016V
0PF
1uF
20
GND
+5V
55Ts
BYV-26G
2200PF
L4
39.2K 1%
L1
30L30
EGP
S
R5*25
1
TL431
10PF
+
+
ER35
20N60
2200uF/6.3V
4.75K 1% 1/8W
2200uF/10V
0
EI10 PC
10
GND
1
PWM IS
0.2/2S)
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
24
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
For Line Sagging Delay Application Circuit (Current Mode)
GBL408
4
L
+
-
1
FG
N
EMI Circuit
IN5406
IN5406
AC INLET
0.22 2W(s)
0.2 2W(s)
1uF/400V
GND
47
1N540
3M1%
1M
1M
VCC
L
B+
2
1
+
22uF/25V
0.1uf/25v
380VDC
0.47UF
600V
13
3
1M 1%
AS27950
VCC ISENSE
VEAO
243K
200K 1%
3M 1%
1000pF
16
N4148
0.47
200
2
4
0.47uF/16V
0.047uF
IAC
1M 1%
36.5K
15
6
0.47uF
+
VFB
Vrms
150uF/450V
10K
20
12
VDC PFCOUT
R16
B
MPS75
4700pF
22K
1
10
V
N222
IEAO
11
8
PWMOUT
14
7
VRERAMP2
PWM OU
470pF
470pF/250V
9
N2907
13K 1%
RAMDCIlim
470pF
PWM
2K 1%
14K 1%
G
SS
5
70
VREF
10K
0.1uF
220
47F
IN4148
ISO1A
817C
1uF
+5V
+12V
ISO1A
10.2K 1%
1000PF
10
817C
L1A
L3
1K
380VDC
ARE)
+12V
PWM OUT
R5*25
20N60
28T
4.7K
0.1uF
+
10
E35
+
2200uF/16V
10K
2200u6V
100
1uF
20
GND
+5V
s
V-26EG
2200PF
L4
39.2K 1%
30
BYV-26EG
12TS
R5*25
1
TL431
1000
+
+
ERL-
20N60
2200uF/6.3V
4.75K 1% 1/8W
2200uF/10V
0
EI10 PC4
10
GND
10K
PWM IS
0.2/2W(
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
25
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
PACKAGE DIMENSION
16-PIN SOP (S16)
θ
6-PN P (P16)
PIN ID
θ
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
26
CM6800T (Turbo-Speed PFC+Green PWM)
http://www.championmicro.com.tw
EPA/85+ PFC+PWM COMBO CONTROLLER
Design for High Efficient Power Supply
IMPORTANT NOTICE
Champion Microelectronic Corporation (CMC) reserves the right to make changes to its products or to
discontinue any integrated circuit product or service without notice, and advises its customers to obtain
the latest version of relevant information to verify, before placing orders, that the information being relied
on is current.
A few applications using integrated circuit products may involve potential risks of death, personal injury,
or severe property or environmental damage. CMC integrated circuit products are not designed,
intended, authorized, or warranted to be suitable for use in life-support applications, devices or systems
or other critical applications. Use of CMC products in such applications is understood to be fully at the
risk of the customer. In order to minimize risks associated with the customer’s applications, the
customer should provide adequate design and operating safeguards.
HsinChu Headquarter
Sales & Marketing
5F, No. 11, Park Avenue II,
Science-Based Industrial Park,
HsinChu City, Taiwan
21F., No. 96, Sec. 1, Sintai 5th Rd., Sijhih City,
Taipei County 22102,
Taiwan, R.O.C.
TEL: +886-3-567 9979
FAX: +886-3-567 9909
T E L : +886-2-2696 3558
F AX: +886-2-2696 3559
http://www.champion-micro.com
2010/08/03 Rev. 1.2
Champion Microelectronic Corporation
27
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