CM6805BO Datasheet, PDF (1/15 Pages) Champion Microelectronic Corp. – 10-PIN Green-Mode PFC/PWM Combo CONTROLLER

CM6805BO
10-PIN Green-Mode PFC/PWM Combo CONTROLLER
GENERAL DESCRIPTION
The CM6805BO is the Green-Mode PFC/PWM Combo
controller for Desktop PC and High Density AC Adapter.
For the power supply, it’s input current shaping PFC
performance could be very close to the performance of the
CM6800 or ML4800 leading edge modulation average
current topology.
CM6805BO offers the use of smaller, lower cost bulk
capacitors, reduces power line loading and stress on the
switching FETs, and results in a power supply fully
compliant to IEC1000-3-2 specifications. The CM6805BO
includes circuits for the implementation of a leading edge
modulation, input current shaping technique “boost” type
PFC and a trailing edge modulation current, PWM.
The CM6805BO’s PFC and PWM operate at the same
frequency, 100kHz. A PFC OVP comparator shuts down
the PFC section in the event of a sudden decrease in load.
The PFC section also includes peak current limiting for
enhanced system reliability.
PFC has a PFCOFFB pin which can use for AC brown out
application and determine the GMth to turn off PFC.
FEATURES
‹ 10-Pin SOIC package.
‹ Use RAC around 4~8 Mega Ohm at IAC pin.
‹ Easy to configure into Boost Follower.
‹ Enable lowest BOM for power supply with PFC.
‹ Internally synchronized PFC and PWM in one IC.
‹ Patented slew rate enhanced voltage error amplifier
with advanced input current shaping technique.
‹ Universal Line Input Voltage
‹ CCM boost or DCM boost with leading edge
modulation PFC using Input Current Shaping
Technique.
‹ Feed forward IAC pin to do the automatic slope
compensation.
‹ PFCOVP, Precision -1V PFC ILIMIT, PFC Tri-Fault
Detect comparator to meet UL1950
‹ Low supply currents; start-up: 100uA typical,
operating current: 2mA typical.
‹ Synchronized leading PFC and trailing edge
modulation PWM to reduce ripple current in the
storage capacitor between the PFC and PWM
sections and to reduce switching noise in the system
‹ VIN-OK Comparator to guarantee to enable PWM
when PFC reach steady state
‹ High efficiency trailing-edge current mode PWM
‹ Exact 50% PWM maximum duty cycle
‹ UVLO, REFOK, and brownout protection
‹ Digital PFC and PWM soft start, ~10mS
‹ Precision PWM 1.5V current limit for current mode
operation
‹ PFCOFFB pin to sense light load to turn off PFC or
PFCOFFB pin to sense Input voltage as AC Brown
Out
2007/11/28 Rev 1.2
Champion Microelectronic Corporation
Page 1