Champion CM6800T General Description Manual

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:

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

11.) Monotonic Output design is easy

12.) And more… Of course, the cost can be reduced

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:

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

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.

 Patents Pending

 Pin to pin compatible with CM6802 family, CM6800

family, and ML4800 family

 23V Bi-CMOS process

 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

 Leading Edge Blanking for both PFC and PWM

 fRTCT = 4*fpfc =4*fpwm for CM6800T

 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

 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

 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

 PDP Power Supply

 IPC Power Supply

 UPS

 Battery Charger

 DC Motor Power Supply

 Monitor Power Supply

 Telecom System Power Supply

 Distributed Power

SOP-16 (S16) / PDIP-16 (P16)

1

2

3

4

5

6

7

8

IEAO

IAC

ISENSE

VRMS

SS

VDC

RAMP1

RAMP2

VEAO

VFB

VREF

VCC

PFC OUT

PWM OUT

GND

DC ILIMIT

16

15

14

13

12

11

10

9

PIN DESCRIPTION

Pin No. Symbol Description

PFC transconductance current error amplifier output

1

2

3

4

I

EAO

I

AC

I

SENSE

V

RMS

(Gmi).

IAC has 2 functions:

1. PFC gain modulator reference input.

2. Typical RAC resistor is about 6 Mega ohm to sense

the line.

PFC Current Sense: for both Gain Modulator and PFC

ILIMIT comparator.

Line Input Sense pin and also, it is the brown out sense

pin.

Operating Voltage

Min. Typ. Max. Unit

0 VREF V

0 100 uA

-1.3 0.7 V

0 8 V

Soft start capacitor pin; it is pulled down by 70K ohm

5 SS

internal resistor when DCILIMIT reach 1V; the power is

limited during the PWM Brown out.

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 VDC

DC to DC PWM voltage feedback input.

RAMP1

7

Oscillator timing node; timing set by RT and CT

(RTCT)

8

RAMP 2

(PWM

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).

RAMP)

9 DC I

LIMIT

10 GND

11 PWM OUT

12 PFC OUT

13 VCC

14 VREF

PWM current limit comparator input

Ground

PWM driver output

PFC driver output

Positive supply for CM6800T

Maximum 3.5mA buffered output for the internal 7.5V

reference when VCC=14V

0 10 V

0.8 4 V

0 V

DCmax

-1.8 V

0 1 V

0 VCC V

0 VCC V

10 15 18 V

7.5 V

15 VFB

16 VEAO

PFC transconductance voltage error amplifier input

PFC transconductance voltage error amplifier output

(GmV)

ORDERING INFORMATION

Part Number Temperature Range Package

CM6800TXIP*

CM6800TXIS*

CM6800TXISTR*

*Note:

X : Suffix for Halogen Free and PB Free Product

TR : Package is Typing Reel

-40℃ to 125℃

-40℃ to 125℃

-40℃ to 125℃

0 2.5 3 V

0 6 V

16-Pin PDIP (P16)

16-Pin Narrow SOP (S16)

16-Pin Narrow SOP (S16)

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)

13

7.5V

REFERENCE

Q

Q

VCC

MPPFC

MNPFC

PPWM

NPFC

VCC

PFC OUT

VCC

PWM OUT

VREF

17V

ZENER

17V

ZENER

14

12

11

VFB

15

IAC

2
4

3

7

8

6

5

VRMS

ISENSE

RAMP1

RAMP2

VDC

VCC

SS

2.5V

10uA

16

GMv

+

.

-

GAIN

MODULATOR

2K

SW SPST

1.8V

70K

VEAO

PFC

Rmul

PFCCLK

PWMCLK

+

-

-

+

-

Rmul

GMi

.

1

IEAO

PFC CMP

+

-

PFC RAMP

.

.

VFB

2.36V

-

+

380V-OK

VFB

2.75V

0.5V
VFB

-1.0V

ISENSE

0.3V

VEAO

Green PWM

.

PFC OVP

+

-

PFC Tri-Fault

+

-

PFC ILIMIT

+

-

Green PFC

+

-

.

16.5V
Zener

SRQ

S

SRQ

SRQ

Q

380-OK

DC ILIMIT

9

GND

10

REF-OK

1.0V

-

+

DC ILIMIT

VCC

UVLO

ABSOLUTE MAXIMUM RATINGS

Absolute Maximum ratings are those values beyond which the device could be permanently damaged.

Parameter Min. Max. Units

VCC 18 V
IEAO 0 VREF+0.3 V
I

Voltage -5 0.7 V

SENSE

PFC OUT
PWMOUT
Voltage on Any Other Pin
I

REF

IAC Input Current

GND – 0.3 VCC + 0.3 V
GND – 0.3 VCC + 0.3 V
GND – 0.3 VCC + 0.3 V

3.5 mA
1 mA

Peak PFC OUT Current, Source or Sink 0.5 A
Peak PWM OUT Current, Source or Sink 0.5 A
PFC OUT, PWM OUT Energy Per Cycle 1.5

Junction Temperature 150
Storage Temperature Range -65 150
Operating Temperature Range -40 125
Lead Temperature (Soldering, 10 sec) 260
Thermal Resistance (θJA)

Plastic DIP
Plastic SOIC

Power Dissipation (PD) TA<50℃

80
105

800 mW

μ

J

℃
℃
℃
℃

℃/W
℃/W

ESD Capability, HBM Model 5.5 KV
ESD Capability, CDM Model 1250 V

2010/08/03 Rev. 1.2 Champion Microelectronic Corporation 4

CM6800T (Turbo-Speed PFC+Green PWM)

μ

μ

μ

μ

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)

CM6800T Symbol Parameter Test Conditions

Unit

Min. Typ. Max.

Clean Digital PFC Brown Out

VRMS Threshold High

VRMS Threshold Low

Hysteresis 710 760 mV

Voltage Error Amplifier (gmv)

Input Voltage Range 0 3 V

Transconductance

Feedback Reference Voltage 2.45 2.52 2.58 V

Input Bias Current Note 2 -1.0 -0.05

Output High Voltage 5.8 6.0 V

Output Low Voltage 0.1 0.4 V

Sink Current

Room Temperature=25℃

Room Temperature=25℃

= V

V

NONINV

Overdrive Voltage = 100mV @ T=25℃

, VEAO = 3.35V @ T=25℃

INV

1.70 1.78 1.86 V

0.98 1.03 1.08 V

25 40 60

-60 -40 -28

mho

A

A

Source Current

Open Loop Gain Guaranteed by design 30 40 dB

Power Supply Rejection Ratio 11V < VCC < 16.5V 60 75 dB

Overdrive Voltage = 100mV @ T=25℃

0.9 3 7

A

2010/08/03 Rev. 1.2 Champion Microelectronic Corporation 5

CM6800T (Turbo-Speed PFC+Green PWM)

μ

μ

μ

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,
T

=Operating Temperature Range (Note 1)

A

CM6800T

Symbol Parameter Test Conditions

Min. Typ. Max.

Current Error Amplifier (gmi)

Unit

Input Voltage Range (Isense pin)

= V

V

Transconductance

Input Offset Voltage VEAO=0V, IAC is open

Output High Voltage

Output Low Voltage

Sink Current

Source Current

Open Loop Gain DC Gain 30 40 dB

Power Supply Rejection Ratio 11V < VCC < 16.5V 60 75 dB

PFC OVP Comparator

Threshold Voltage 2.60 2.75 2.85 V

Hysteresis 130 220 mV

PFC Green Power Detect Comparator

NONINV

= -0.5V, IEAO = 1.5V @ T=25℃

I

SENSE

= +0.5V, IEAO = 4.0V @ T=25℃

I

SENSE

, IEAO = 1.5V @ T=25℃

INV

-1.2 0.7 V

50 67 85

-10 50 mV

6.8 7.4 7.7 V

0.1 0.4 V

-40 -34 -28

27 32 37

mho

A

A

Veao Threshold Voltage 0.14 0.26 0.4 V

Tri-Fault Detect

Fault Detect HIGH 2.70 2.85 3.0 V

Time to Fault Detect HIGH V

Fault Detect Low 0.1 0.28 0.4 V

PFC I

Comparator

LIMIT

Threshold Voltage -1.35 -1.25 -1.15 V

(PFCI

Output)

Delay to Output (Note 4) Overdrive Voltage = -100mV 700 ns

– Gain Modulator

LIMIT

FB=VFAULT DETECT LOW

=OPEN, 470pF from VFB to GND

V

FB

to

2 4 ms

300 450 mV

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,
T

=Operating Temperature Range (Note 1)

A

Symbol Parameter Test Conditions

CM6800T

Unit

Min. Typ. Max.

DC I

Comparator

LIMIT

Threshold Voltage 0.92 1.0 1.08 V

Delay to Output (Note 4) Overdrive Voltage = 100mV 700 ns

DC to DC PWM Brown Out Comparator

OK Threshold Voltage 2.1 2.3 2.5 V

Hysteresis 880 950 1000 mV

GAIN Modulator

Gain1 (Note 3)

Gain2 (Note )3

Gain3 (Note 3)

Gain4 (Note 3)

Bandwidth (Note 4)

Output Voltage = Rmul *

(I

SENSE-IOFFSET

)

= 20μA, V

I

AC

T=25℃ SS<VREF

= 20μA, V

I

AC

2.375V @ T=25℃ SS<VREF

= 20μA, V

I

AC

T=25℃ SS<VREF

= 20μA, V

I

AC

@ T=25℃ SS<VREF

I

= 50μA, V

AC

SS<VREF

=1.125, VFB = 2.375V @

RMS

= 1.45588V, VFB=

RMS

=2.91V, VFB = 2.375V @

RMS

= 3.44V, VFB = 2.375V

RMS

= 40μA

I

AC

= 1.125V, VFB = 2V

RMS

4.4 5.5 6.6

4 5 6

1.2 1.5 1.8

0.9 1.05 1.3

1 MHz

0.74 0.8 0.86 V

Oscillator (Measuring fpfc)

= 5.88 kΩ, CT = 1000pF, TA = 25℃

R

Initial fpfc Accuracy 1

T

64 68 72 kHz

IAC=0uA

Voltage Stability 11V < VCC < 16.5V 2 %

Temperature Stability 2 %

Total Variation Line, Temp 60 75 kHz

Ramp Valley to Peak Voltage VEAO=6V and IAC=20uA 2.5 V

PFC Dead Time (Note 4) 550 950 ns

CT Discharge Current V

RAMP2

= 0V, V

= 2.5V 10 11 12 mA

RAMP1

2010/08/03 Rev. 1.2 Champion Microelectronic Corporation 7

CM6800T (Turbo-Speed PFC+Green PWM)

μ

μ

μ

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, R

Symbol Parameter Test Conditions

Reference

Output Voltage

Line Regulation

Temperature Stability 0.4 %
Total Variation Line, Load, Temp 7.3 7.7 V

Long Term Stability

PFC

Minimum Duty Cycle IEAO > 4.5V 0 %
Maximum Duty Cycle V

Rise/Fall Time (Note 4)

PWM

Duty Cycle Range 0-49.5 0-50 %

Rise/Fall Time (Note 4) CL = 100pF 50 ns

PWM Comparator Level Shift

Soft Start

Soft Start Current

Soft Start Discharge Current Vrms=0.926V, Soft Start=8V 0.5 3 6

Supply

Start-Up Current

Operating Current 14V, CL = 0 2.5 3.5 mA
Turn-on Undervoltage Lockout Threshold CM6800T 12.35 12.85 13.65 V
Turn-off Undervoltage Lockout Threshold CM6800T 9.75 10.25 V
Turn-off Undervoltage Lockout Hysteresis CM6800T 2.8 2.95 3.1 V

Shunt Regulator (VCC zener)

= 5.88 kΩ, CT = 1000pF, TA=Operating Temperature Range (Note 1)

T

Load Regulation

Output Low Rdson

Output High Rdson

Output Low Rdson

Output High Rdson

CM6800T

Min. Typ. Max.

= -45℃~85℃, I(VREF) = 0~3.5mA

T

A

11V < V

< 16.5V@ T=25℃

CC

VCC=10.5V,0mA < I(VREF) < 2mA;
@ T=25℃

VCC=14V,0mA < I(VREF) < 3.5mA;
TA = -40℃~85℃

= 125℃, 1000HRs

T

J

< 1.2V 93 95 %

IEAO

= -20mA @ T=25℃

I

OUT

= -100mA @ T=25℃

I

OUT

= 10mA, VCC = 9V @ T=25℃

I

OUT

= 20mA @ T=25℃

I

OUT

= 100mA @ T=25℃

I

OUT

= 100pF @ T=25℃

C

L

= -20mA @ T=25℃

I

OUT

= -100mA @ T=25℃

I

OUT

I

= 10mA, VCC = 9V 0.5 1 V

OUT

= 20mA @ T=25℃

I

OUT

= 100mA @ T=25℃

I

OUT

@ T=25℃

Room Temperature=25℃

= 12V, CL = 0 @ T=25℃

V

CC

7.3 7.5 7.7 V

3 5 mV

25 50 mV

25 50 mV

5 25 mV

13 18 ohm

18 ohm

0.5 1 V

24 30 ohm

40 ohm

50 ns

13 18 ohm

18 ohm

26.5 40 ohm

40 ohm

1.6 1.8 2 V

7 10 12

50 65

Unit

Zener Threshold Voltage Apply VCC with Iop=20mA 16.15 17 17.85 V

A

A

A

Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst-case test conditions.

Note 2: Includes all bias currents to other circuits connected to the V

Note 3: Gain ~ K x 5.3V; K = (I

SENSE

– I

) x [IAC (VEAO – 0.7)]-1; VEAO

OFFSET

FB

pin.

MAX

= 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/div.
Ch2 is VCC,Ch3 is SS(soft start pin),CH4 is Vo(12V).

Output 10% and 20% load turn on waveform at 230Vac Output 50% and 100% load turn on waveform at 230Vac

Ch1 is 380V bulk cap voltage which is 100V/div. Ch1 is 380V bulk cap voltage which is 100V/div.
Ch2 is VCC,Ch3 is SS(soft start pin),CH4 is Vo(12V) 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. Ch1 is 380V bulk cap voltage which is 100V/div.
Ch2 is VCC,Ch3 is SS(soft start pin),CH4 is Vo(12V) 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 is PFC stage Mosfet Drain current(zoom In)
Ch3 is PFC stage Mosfet drain current, CH4 is Vo(12V)

90VAC 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)

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. Ch3 is PFC stage Mosfet Drain current (zoom In)
Ch3 is PFC stage Mosfet drain current, CH4 is Vo (12V)

230VAC turn on 500ms turn off 100ms 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)

230VAC 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/div. Ch3 is PFC stage Mosfet Drain current
Ch3 is PFC stage Mosfet drain current, CH4 is Vo (12V)

(zoom In)

230VAC turn on 500ms turn off 10ms 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 13

CM6800T (Turbo-Speed PFC+Green PWM)

http://www.championmicro.com.tw EPA/85+ PFC+PWM COMBO CONTROLLER

Design for High Efficient Power Supply

Getting Start:

Power Factor Correction

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
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.

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.

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.

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
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.

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
used value is 385VDC, to allow for a high line of 270VAC
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.

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:

rms

.

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Dynamic Soft PFC (patent pending)

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.

PFC Section:

Gain Modulator

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:

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 I

AC

.
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.

K=Gain/(VEAO-0.7V)

I

= K x (VEAO – 0.7V) x IAC

mul

Where K is in units of [V

-1

Note that the output current of the gain modulator is limited

around 100

A and the maximum output voltage of the gain

modulator is limited to 100uA x 7.75K≒0.8V. This 0.8V also
will determine the maximum input power.

However, I

= I

I

SENSE

GAINMOD-IOFFSET

cannot be measured directly from I

GAINMOD

when VEAO is less than 0.5V and I
I

is around 25uA.

OFFSET

IAC=20uA, Veao=6V

Gain=Imul/Iac

]

and I

OFFSET

SENSE

can only be measured

GAINMOD

is 0A. Typical

.

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 V

2

. The relationship between V

RMS

and gain is

RMS

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.

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:

mul

=

I

AC

V

RMS

0.7V)-VEAOI (×

2

x constant (1)

Gain vs. VRMS (pin4)

When VRMS below 1V, the PFC is shut off. Designer needs

to design 80VAC with VRMS average voltage=

II

=Gain

OFFSETSENSE

I

AC

I

=

MUL

I

1.14V.

AC

Selecting R

for IAC pin

AC

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.

=Vin min peak x 53.03K. For example, if the minimum line

R

AC

voltage is 80VAC, the RAC=80 x 1.414 x 53.03K = 6 Mega ohm.

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Vrms Description:

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:

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 corresponds to
70Vac). When the Vrms voltage reaches 1.75V (The On Vin
voltage usually corresponds to 86.6V and when Vin = 80Vac,
Vrms = 1.14V), PFC is on.

Before PFC is turned on, Vrms (pin 4) represents the peak
voltage of the AC input. Before PFC is turned off, Vrms (pin 4)
represents the Vrms voltage of the AC input.

Current Error Amplifier, IEAO

Cycle-By-Cycle Current Limiter and

Selecting R

The I
feedback loop, is a direct input to the cycle-by-cycle current
limiter for the PFC section. Should the input voltage at this pin
ever be more negative than –1V, the output of the PFC will be
disabled until the protection flip-flop is reset by the clock pulse
at the start of the next PFC power cycle.

is the sensing resistor of the PFC boost converter. During

R

S

the steady state, line input current x R
Since the maximum output voltage of the gain modulator is I
max x 7.75K≒ 0.8V during the steady state, R

input current will be limited below 0.8V as well. When VEAO
reaches maximum VEAO which is 6V, Isense can reach 0.8V.
At 100% load, VEAO should be around 4.5V and ISENSE
average peak is 0.6V. It will provide the optimal dynamic
response + tolerance of the components.

Therefore, to choose R

R

+ R

SENSE

For example, if the minimum input voltage is 80VAC, and the
maximum input rms power is 200Watt, R
(0.6V x 80V x 1.414) / (2 x 200) = 0.169 ohm. The designer
needs to consider the parasitic resistance and the margin of
the power supply and dynamic response. Assume R

0.03Ohm, R

pin, as well as being a part of the current

SENSE

Parasitic

SENSE

SENSE

= I

SENSE

, we use the following equation:

SENSE

x 7.75K.

mul

SENSE

=0.6V x Vinpeak / (2 x Line Input power)

+ R

SENSE

= 0.139Ohm.

x line

Parasitic

Parasitic

PFC OVP

mul

=

=

The current error amplifier’s output controls the PFC duty
cycle to keep the average current through the boost inductor a
linear function of the line voltage. At the inverting input to the
current error amplifier, the output current of the gain modulator
is summed with a current which results from a negative voltage
being impressed upon the I
I

represents the sum of all currents flowing in the PFC

SENSE

pin. The negative voltage on

SENSE

circuit, and is typically derived from a current sense resistor in
series with the negative terminal of the input bridge rectifier.

In higher power applications, two current transformers are
sometimes used, one to monitor the IF of the boost diode. As
stated above, the inverting input of the current error amplifier is
a virtual ground. Given this fact, and the arrangement of the
duty cycle modulator polarities internal to the PFC, an increase
in positive current from the gain modulator will cause the
output stage to increase its duty cycle until the voltage on

is adequately negative to cancel this increased current.

I

SENSE

Similarly, if the gain modulator’s output decreases, the output
duty cycle will decrease, to achieve a less negative voltage on

SENSE

pin.

the I

In the CM6800T, PFC OVP comparator serves to protect the
power circuit from being subjected to excessive voltages if the
load should suddenly change. A resistor divider from the high
voltage 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.

The Current Loop Gain (S)

ΔV

ISENSE

=

≈

ΔD

OUTDC

OFF

ΔD

OFF

*

EAO

ΔI

R*V

S

2.5V*L*S

EAO

ΔI

*

SENSE

ΔI

CI

Z*GM*

I

: Compensation Net Work for the Current Loop

Z

CI

GM

: Transconductance of IEAO

I

V

: PFC Boost Output Voltage; typical designed value is

OUTDC

380V and we use the worst condition to calculate the Z

R

: The Sensing Resistor of the Boost Converter

SENSE

CI

2.5V: The Amplitude of the PFC Leading Edge Modulation
Ramp(typical)
L: The Boost Inductor

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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 V

to produce a soft-start

REF

characteristic on the PFC: as the reference voltage comes up
from zero volts, it creates a differentiated voltage on I

EAO

which
prevents the PFC from immediately demanding a full duty
cycle on its boost converter.

PFC Voltage Loop

There are two major concerns when compensating the
voltage loop error amplifier, V
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).

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)

2

*

ΔV

ΔV

IN

FB

*

OUT

2.5V*P

=

≈

ΔV
ΔV

OUTDC

OUT

EAO

; stability and transient

EAO

EAO

ΔV

FB

ΔV

C*S*ΔV*V

DCEAO

CVV

Z*GM*

The gain vs. input voltage of the CM6800T’s voltage error

amplifier, V

has a specially shaped non-linearity such that

EAO

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 (V
I

Filter, the RC filter between R

SENSE

There are 2 purposes to add a filter at I

FB

) to

SENSE

and I

SENSE

SENSE

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 I

SENSE

Filter to attenuate the energy.

2.) To reduce L, the Boost Inductor: The I
reduce L, the Boost Inductor: The I

SENSE

reduce the Boost Inductor value since the I
behaves like an integrator before going I

SENSE

Filter To

SENSE

Filter also can

Filter

SENSE

which is the

input of the current error amplifier, IEAO.

The I
Filter is between 100 ohm and 50 ohm because I

Filter is a RC filter. The resistor value of the I

SENSE

OFFSET

SENSE

x the
resistor can generate an offset voltage of IEAO. By selecting
R
than 5mV. Usually, we design the pole of I

equal to 50 ohm will keep the offset of the IEAO less

FILTER

SENSE

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 I
Filter, C

, will be around 381nF.

FILTER

SENSE

ZCV: Compensation Net Work for the Voltage Loop
GM

: Transconductance of VEAO

v

P

: Average PFC Input Power

IN

V

: PFC Boost Output Voltage; typical designed value is

OUTDC

380V.

CDC: PFC Boost Output Capacitor
PFC Current Loop

The current transcondutance amplifier, GMi, I
compensation is similar to that of the voltage error amplifier,
V

with exception of the choice of crossover frequency.

EAO

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.

EAO

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VFB

15

IAC

2

VRMS

4

ISENSE

3

RAMP1

7

2.5V

16

GMv

+

.

-

GAIN

MODULATOR

VEAO

PFC

Rmu l

PFCCLK

+

-

Rmul

1

IEAO

VFB

0.5V
VFB

-1.0V

ISENSE

0.3V

VEAO

2.75V

GMi

.

PFC CMP

+

-

PFC RAMP

.

Figure 1. PFC Section Block Diagram

PFC OVP

+

-

PFC Tri-Fault

+

-

PFC ILIMIT

+

-

Green PFC

+

-

.

16.5V
Zener

SRQ

SRQ

13

7.5V

REFERENCE

Q

Q

VCC

MPPFC

MNPFC

VCC

VREF

PFC OUT

17V

ZENER

14

12

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Oscillator (RAMP1, or called RTCT)

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:

fRTCT =

1

DEADTIMERAMP tt

+

The dead time of the oscillator is derived from the
following equation:

1.25V

−

t

RAMP

= CT x RT x In

REF

REF

3.75V

−

at VREF = 7.5V:

t

= CT x RT x 0.51

RAMP

The dead time of the oscillator may be determined using:

t

DEADTIME

The dead time is so small (t

=

2.5V

3.64mA

x CT = 686.8 x CT

>> t

RAMP

DEADTIME

) that the

operating frequency can typically be approximately by:

fRTCT =

1

RAMPt

Ct should be greater than 470pF.

Let us use 1000PF Solving for R
standard components values, C

yields 5.88K. Selecting

T

= 1000pF, and RT=

T

5.88kΩ

The dead time of the oscillator determined two things:

1.) PFC minimum off time which is the dead time

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.

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.

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. DCI

, which provides cycle-by-cycle current limiting, is

LIMIT

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 V

will be compared.

DC

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 I

input is used for output

LIMIT

stage over-current protection.

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 V

to command a zero

DC

percent duty cycle for input voltages below around 1.8V.

PWM Current Limit (DCILIMIT)

The DC I
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.

pin is a direct input to the cycle-by-cycle current

LIMIT

PWM Brown Out (380V-OK Comparator)

The 380V-OK comparator monitors the DC output of the PFC
and inhibits the PWM if this voltage on V

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.

is less than its nominal

FB

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PWM Control (RAMP2)

When the PWM section is used in current mode, RAMP2 is
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
(R

RAMP2

, C

),that will have a minimum value of zero volts

RAMP2

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.

Soft Start (SS)

Start-up of the PWM is controlled by the selection of the
external capacitor at SS. A current source of 10

μ A supplies

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:

C

SS

= t

DELAY

x

A10

1.8V

where C
is the desired start-up delay.

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 C

CSS = 5ms x

is the required soft start capacitance, and the t

SS

:

SS

A10

≒ 27nF

DEALY

1.8V

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 V

at start-up is related both to

FB

line voltage and nominal PFC output voltage. Typically, a

μ F soft start capacitor will allow time for V

0.05

and PFC

FB

out to reach their nominal values prior to activation of the
PWM section at line voltages between 90Vrms and 265Vrms.

Generating VCC

A filter network is recommended between VCC (pin 13) and
bootstrap winding. The resistor of the filter can be set as
following.

x I

R

FILTER

VCC

~ 2V, I

= IOP + (Q

VCC

PFCFET

+ Q

PWMFET

) x fsw

IOP = 3mA (typ.)

EXAMPLE:

With a wanting voltage called, V

,of 18V, a VCC of 15V

BIAS

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:

I

GATEDRIVE

= 100kHz x 90nC = 9mA

CCBIAS

R

R

BIAS

BIAS

=

=

VV

GCC

II

15V18V
9mA 5mA

Choose R

BIAS

= 214Ω

The CM6800T should be locally bypassed with a 1.0μF

ceramic capacitor. In most applications, an electrolytic
capacitor of between 47μF and 220μF is also required

across the part, both for filtering and as part of the start-up
bootstrap circuitry.

Leading/Trailing Modulation

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.

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.

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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-cycle
of the leading edge modulation is determined during OFF time
of the switch.

Figure 5 shows a leading edge control scheme.
One of the advantages of this control technique is that it
required only one system clock. Switch 1(SW1) turns off and
switch 2 (SW2) turns on at the same instant to minimize the
momentary “no-load” period, thus lowering ripple voltage
generated by the switching action. With such synchronized
switching, the ripple voltage of the first stage is reduced.
Calculation and evaluation have shown that the 120Hz
component of the PFC’s output ripple voltage can be reduced
by as much as 30% using this method.

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)

3

IN5406

IN5406

0.22 2W(s)

GND

470pF

0.2 2W(s)

380VDC

1M 1%

1M 1%

13K 1%

GBL408

4

1uF/400V

1000pF

+

-

1

2

VCC

22uF/25V

0.47uF/16V

4700pF

22K

470pF

2K 1%

14K 1%

VREF

470pF

0.1uF

ISO1A

817C

2.49K 1%

+

200K 1%

0.047uF

0.1uf/25v

EMI Circuit

47

16

VEAO

15

VFB

6

VDC

PFC O U T

1

IEAO

PWM O U T

14

VREF

7

RAMP1

GND S S

10 5

ISENSEVCC

RAMP2

DCIlim

313

IAC

Vrms

0.047uF

820pF

2

1000pF

4

12

11

8

9

3M1%

3M 1%

30.1K

470

2200PF

PWM IS

0.47UF

0.47uF

L
FG

N

AC INLET

1M

1M

243K

36.5K

2N2222

2N2907

VCC

0.47uF

R16

10

PWM OUT

1N4148

B

L 1

APS27950

20

E

MPS 751

C

1N5406

1

10K

2 1

32

20N60

8A/600V

B+

+

150uF/450V

470pF/250V

PWM OUT

PWM IS

380VDC

1uF

20

EI10 PC40

+5V

1000PF

10

10

1000PF

L1A

28TS

2200uF/16V

L1B

12TS

2200uF/10V

10

20N60

10K

BYV-26EGP

BYV-26EGP

10

20N60

10K

ERL-35

55Ts

ERL-35

0.2/2W (S)

(SPAR E)

30L30

1000PF

10

L3

R5*25

+

L4

R5*25

+

+

2200uF/16V

+

2200uF/6. 3V

GND

+12V

GND

+5V

39.2K 1%

4.75K 1% 1/8W

10.2K 1%

4.7K

2200PF

0.1uF

+12V

ISO1A

817C

1K

1

TL431

2 3

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)

3

IN5406

IN5406

0.22 2W (s)

GND

470pF

0.2 2W(s)

380VDC

1M 1%

1M 1%

13K 1%

GBL408

4

1uF/400V

1000pF

+

-

1

2

VCC

22uF/25V

0.47uF/16V

4700pF

22K

470pF

2K 1%

14K 1%

VREF

470pF

0.1uF

ISO1A

817C

2.49K 1%

+

200K 1%

0.047uF

0.1uf/25v

EMI Circuit

10K

IN4148

47

3M1%

313

3M 1%

ISENSEVCC

16

VEAO

2

IAC

VFB

VDC

IEAO

VREF

RAMP1

GND SS

10 5

PFC O U T

PWM O U T

RAMP2

DCIlim

1000pF

4

Vrms

1uF

820pF

30.1K

12

11

8

470

9

PWM IS

2200PF

15

6

1

14

7

0.47UF

0.47uF

L
FG

N

AC INLET

1M

1M

243K

36.5K

2N2222

2N2907

VCC

0.47uF

R16

10

PWM OUT

1N4148

B

L 1

APS27950

20

E

MPS 751

C

1N5406

1

10K

2 1

32

20N60

8A/600V

B+

+

150uF/450V

470pF/250V

PWM OUT

PWM IS

380VDC

1uF

20

EI10 PC40

+5V

1000PF

10

10

1000PF

L1A

28TS

2200uF/16V

L1B

12TS

2200uF/10V

10

20N60

10K

BYV-26EGP

BYV-26EGP

10

20N60

10K

ERL-35

55Ts

ERL-35

0.2/2W (S)

(SPA RE)

30L30

1000PF

10

L3

R5*25

+

L4

R5*25

+

+

2200uF/16V

+

2200uF/6. 3V

GND

+12V

GND

+5V

39.2K 1%

4.75K 1% 1/8W

10.2K 1%

4.7K

2200PF

0.1uF

+12V

ISO1A

817C

1K

1

TL431

2 3

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)

3

IN5406

IN5406

0.22 2W(s)

GND

470pF

0.2 2W(s)

380VDC

1M 1%

1M 1%

13K 1%

GBL408

4

1uF/400V

1000pF

+

-

1

2

VCC

22uF/25V

0.47uF/16 V

4700pF

22K

470pF

2K 1%

14K 1%

VREF

0.1uF

ISO1A

817C

2.49K 1%

+

200K 1%

0.047uF

470pF

0.1uf/25v

EMI Circuit

47

16

VEAO

15

VFB

6

VDC

PFC O U T

1

IEAO

PWM O U T

14

VREF

7

RAMP1

GND SS

10 5

ISENSEVCC

RAMP2

DCIlim

313

IAC

Vrms

0.047uF

3M1%

0.47UF

3M 1%

2

1000pF

4

12

11

8

9

470

2200PF

0.47uF

PWM IS

L

FG

N

AC INLET

1M

1M

243K

36.5K

2N2222

2N2907

0.47uF

VCC

PWM OUT

1N5406

L 1

APS27950

1N4148

R16

10

E

B

C

20

MPS751

2 1

8A/600V

32

20N60

1

10K

B+

+

150uF/450V

470pF/250V

PWM OUT

PWM IS

380VDC

1uF

20

EI10 PC40

+5V

1000PF

10

10

1000PF

L1A

28TS

2200uF/16V

L1B

12TS

2200uF/10V

10

20N60

10K

BYV-26EGP

BYV-26EGP

10

20N60

10K

ERL-35

55Ts

ERL-35

0.2/2W (S)

(SPAR E)

30L30

1000PF

10

L3

R5*25

+

L4

R5*25

+

+

2200uF/16V

+

2200uF/6. 3V

GND

+12V

GND

+5V

39.2K 1%

4.75K 1% 1/8W

10.2K 1%

4.7K

2200PF

0.1uF

+12V

ISO1A

817C

1K

1

TL431

2 3

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)

3

IN5406

IN5406

0.22 2W (s)

GND

470pF

0.2 2W (s)

380VDC

1M 1%

1M 1%

13K 1%

GBL408

4

1uF/400V

1000pF

+

-

1

2

VCC

22uF/25V

0.47uF/ 16V

4700pF

22K

470pF

2K 1%

14K 1%

VREF

0.1uF

ISO1A

817C

2.49K 1%

+

200K 1%

0.047uF

470pF

0.1uf/25v

EMI Circuit

16

15

14

10K

IN4148

47

3M1%

313

ISENSEVCC

VEA O

IAC

VFB

Vrms

6

VDC

PFC OUT

1

IEAO

PWM O U T

VREF

RAMP2

7

RAMP1

DCIlim

GND SS

10 5

1uF

0.47UF

3M 1%

2

1000pF

4

12

11

8

9

470

2200PF

0.47uF

PWM IS

L

FG
N

AC INLET

1M

1M

243K

36.5K

2N2222

2N2907

0.47uF

VCC

PWM OUT

1N5406

L 1

APS27950

1N4148

R16

10

E

B

C

20

MPS751

2 1

8A/600V

32

20N60

1

10K

B+

+

150uF/450V

470pF/250V

380VDC

PWM OUT

PWM IS

+5V

1000PF

10

10

1000PF

L1A

28TS

2200uF/16V

L1B

12TS

2200uF/10V

10

1uF

20

EI10 PC40

20N60

10K

BYV-26EGP

BYV-26EGP

10

20N60

10K

ERL-35

55Ts

ERL-35

0.2/2W (S)

(SPARE)

30L30

1000PF

10

L3

R5*25

+

L4

R5*25

+

+

2200uF/16V

+

2200uF/6. 3V

GND

+12V

GND

+5V

39.2K 1%

4.75K 1% 1/8W

10.2K 1%

4.7K

2200PF

0.1uF

1

+12V

ISO1A

817C

1K

TL431

2 3

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

PIN 1 ID

θ

16-PIN PDIP (P16)

θ

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.

T E L : [phone] T E L : [phone]
FA X: [phone] F A X : [phone]
http://www.champion-micro.com

2010/08/03 Rev. 1.2 Champion Microelectronic Corporation 27