CM6900
PFC/PWM C
OMBO
w/ I
NRUSH
C
URRENT
C
ONTROL
& S
EPARATED
PFCOVP
2003/04/23
Preliminary
Rev. 1.2
Champion Microelectronic Corporation
Page 1
GENERAL DESCRIPTION
FEATURES
! Patent Filed #5,565,761, #5,747,977, #5,742,151,
#5,804,950, #5,798,635
!
Inrush Current Control
!
Separated PFC OVP pin
!
Separated Power VCCA and Analog VCCA
!
Separated Power Ground and Analog Ground
!
Additional folded-back current limit for PWM section.
!
23V Bi-CMOS process
!
VIN OK guaranteed turn on PWM at 2.5V instead of 1.5V
!
Internally synchronized leading edge PFC and trailing edge
PWM in one IC
!
Slew rate enhanced transconductance error amplifier for
ultra-fast PFC response
!
Low start-up current (100A typ.)
!
Low operating current (3.0mA type.)
!
Low total harmonic distortion, high PF
!
Reduces ripple current in the storage capacitor between the
PFC and PWM sections
!
Average current, continuous or discontinuous boost leading
edge PFC
!
VCCA OVP Comparator
!
Low Power Detect Comparator
!
PWM configurable for current mode or voltage mode
operation
!
Current fed gain modulator for improved noise immunity
!
Brown-out control, over-voltage protection, UVLO, and soft
start, and Reference OK
The CM6900 is a controller for power factor corrected,
switched mode power suppliers. Power Factor Correction
(PFC) allows the use of smaller, lower cost bulk capacitors,
reduces power line loading and stress on the switching
FETs, and results in a power supply that fully compiles with
IEC-1000-3-2 specifications. Intended as a BiCMOS
version of the industry-standard ML4824, CM6900 includes
circuits for the implementation of leading edge, average
current, "boost" type power factor correction and a trailing
edge, pulse width modulator (PWM). The CM6900 has
additional features besides all the features of CM6800.
Additional features are Inrush Current Control, Separated
PFC OVP pin, Separated Power VCCA pin and Analog
VCCA pin, and Separated Power Ground pin and Analog
Ground pin. Gate-driver with 1A capabilities minimizes the
need for external driver circuits. Low power requirements
improve efficiency and reduce component costs.
An over-voltage comparator shuts down the PFC section in
the event of a sudden decrease in load. The PFC section
also includes peak current limiting and input voltage
brownout protection. The PWM section can be operated in
current or voltage mode, at up to 250kHz, and includes an
accurate 50% duty cycle limit to prevent transformer
saturation.
24 Hours Technical Support---WebSIM
Champion provides customers an online circuit simulation tool
called WebSIM. You could simply logon our website at
www.champion-micro.com for details.
CM6900
PFC/PWM C
OMBO
w/ I
NRUSH
C
URRENT
C
ONTROL
& S
EPARATED
PFCOVP
2003/04/23
Preliminary
Rev. 1.2
Champion Microelectronic Corporation
Page 2
APPLICATIONS
PIN CONFIGURATION
!
Desktop PC Power Supply
!
Internet Server Power Supply
!
IPC Power Supply
!
UPS
!
Battery Charger
!
DC Motor Power Supply
!
Monitor Power Supply
!
Telecom System Power Supply
!
Distributed Power
SOP-20 (S20) / PDIP-20 (P20)
Top View
1
2
3
4
5
6
7
8
20
19
18
17
16
15
14
13
IEAO
I
AC
I
SENSE
V
RMS
INRUSHSTOPB
SS
V
DC
RAM P1
VEAO
V
FB
V
FB2
V
REF
V
CCA
V
DDD
PFCOUT
PW M OU T
V
SSD
AGN D
RAM P2
DC I
LIMIT
9
10
11
12
PIN DESCRIPTION
Operating Voltage
Pin No.
Symbol
Description
Min. Typ.
Max.
Unit
1
IEAO
PFC transconductance current error amplifier output
0
4.25
V
2 I
AC
PFC gain control reference input
0
1
mA
3 I
SENSE
Current sense input to the PFC current limit comparator
-5
0.7
V
4 V
RMS
Input for PFC RMS line voltage compensation
0
6
V
5 INRUSHSTO
PB
Inrush Current Control pin, It is low when Inrush current is high
or during the start-up condition and it is VCCA when Inrush
condition has been removed.
0 VCCA V
6
SS
Connection point for the PWM soft start capacitor
0
VREF+0.7
V
7
V
DC
PWM voltage feedback input
0
VREF+0.7
V
8
RAMP 1
(RTCT)
Oscillator timing node; timing set by RT CT
1.2
3.9
V
9 RAMP
2
(PWM RAMP)
When in current mode, this pin functions as the current sense
input; when in voltage mode, it is the PWM input from PFC
output (feed forward ramp).
0
VREF+0.7
V
10 DC
I
LIMIT
PWM current limit comparator input
0
1
V
11 AGND
Analog
Ground
12 V
SSD
Digital
Ground
13
PWM OUT
PWM driver output
0
VDDD
V
14
PFC OUT
PFC driver output
0
VDDD
V
CM6900
PFC/PWM C
OMBO
w/ I
NRUSH
C
URRENT
C
ONTROL
& S
EPARATED
PFCOVP
2003/04/23
Preliminary
Rev. 1.2
Champion Microelectronic Corporation
Page 4
ORDERING INFORMATION
Part Number
Temperature Range
Package
CM6900IP
-40 to 125
20-Pin PDIP (P20)
CM6900IS
-40 to 125
20-Pin Wide SOP (S20)
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum ratings are those values beyond which the device could be permanently damaged.
Parameter Min.
Max.
Units
V
CCA
and P
VDD
23
V
IEAO
0 4.5 V
I
SENSE
Voltage
-5
0.7
V
PFC OUT
GND 0.3
VCCA + 0.3
V
PWMOUT
GND 0.3
VCCA + 0.3
V
INRUSHSTOPB
GND 0.3
VCCA + 0.3
V
Voltage on Any Other Pin
GND 0.3
VREF + 0.3
V
I
REF
10
mA
I
AC
Input Current
1
mA
Peak PFC OUT Current, Source or Sink
1
A
Peak PWM OUT Current, Source or Sink
1
A
PFC OUT, PWM OUT Energy Per Cycle
1.5
J
Junction Temperature
150
Storage Temperature Range
-65
150
Operating Temperature Range
-40
125
Lead Temperature (Soldering, 10 sec)
260
Thermal Resistance (
JA
)
Plastic DIP
Plastic SOIC
80
105
/W
/W
ELECTRICAL CHARACTERISTICS
Unless otherwise stated, these specifications apply VCCA=+15V,
R
T
= 52.3k, C
T
= 470pF, T
A
=Operating Temperature Range (Note 1)
CM6900
Symbol Parameter
Test
Conditions
Min. Typ. Max.
Unit
Voltage Error Amplifier (g
mv
)
Input Voltage Range
0
5
V
Transconductance
V
NONINV
= V
INV
, VEAO = 3.75V
30
65
90
mho
Feedback Reference Voltage
2.45
2.5
2.55
V
Input Bias Current
Note 2
-1.0
-0.5
A
Output High Voltage
5.8
6.0
V
Output Low Voltage
0.1
0.4
V
Sink
Current
V
FB
= 3V, VEAO = 6V
-35
-20
A
Source
Current
V
FB
= 1.5V, VEAO = 1.5V
30
40
A
Open Loop Gain
50
60
dB
Power Supply Rejection Ratio
11V < V
CCA
< 16.5V
50
60
dB
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