CM6565 Datasheet, PDF (11/19 Pages) Champion Microelectronic Corp. – Noise Free 16 pin Self-Start Interleaved PFC with 180 Degree Phase Shift CRM PFC Controller for 90+/85+

CM6565
Noise Free 16 pin Self-Start Interleaved PFC with
180 Degree Phase Shift CRM PFC Controller for 90+/85+
IAC (PIN 1):
IAC serves several functions:
During the system Start-Up, IAC pin is connected to VCC; therefore, the external RAC which is between IAC and
line input voltage can be served as a Start-Up resistor (bleed resistor). Once VCC is greater than UVLO, 13V, IAC
pin will be connected to the multiplier input which is a current mirror and IAC voltage is about 1.4V.
Usually, the value of the RAC is between 4 Mohm to 10 Mohm.
Green Mode with Fast Start Up with high voltage bipolar and low voltage diode.
The following circuit can be used for the Fast Start Up, if the on time needs to be less than 100mS and Green Mode
Performance is needed.
Line Input Voltage
RAC 1
4M
RAC 2
100K
RIVCCLIMIT
50K
Q1
NPN
DLOWVOLTAGE
IAC
VCC
After VCC is greater than UVLO, IAC is connected to the input of the current mirror which is also the input of the
multiplier. This current input multiplier is less sensitive to the noise since it is sensing current instead of the voltage,
not like the conventional voltage input multiplier which senses the voltage and requires a two resistor network to
sense the line input voltage information.
2008/10/09 Rev1.0
Champion Microelectronic Corporation
Page 11