FAN7528 Datasheet, PDF (1/21 Pages) Fairchild Semiconductor – Dual Output Critical Conduction Mode PFC Controller

December 2005
FAN7528
Dual Output Critical Conduction Mode PFC Controller
Features
• Low Total Harmonic Distortion (THD)
• Dual Output Voltage Control
• Precise Adjustable Output Over Voltage Protection
• Open-feedback Protection and Disable Function
• Zero Current Detector
• 160us Internal Start-up Timer
• MOSFET Over Current Protection
• Under Voltage Lock Out with 3.5V Hysteresis
• Low Start-up (40uA) and Operating Current (1.5mA)
• Totem Pole Output with High State Clamp
• ±400mA Peak Gate Drive Current
• 8-pin DIP or 8-pin SOP
Applications
• Adapter
Related Application Notes
• AN6012 - Design of Power Factor Correction Circuit Using
FAN7528
Description
The FAN7528 is an active power factor correction (PFC) con-
troller for boost PFC applications which operates in the critical
conduction mode (CRM). It uses the voltage mode PWM that
compares an internal ramp signal with the error amplifier output
to generate MOSFET turn-off signal. Because the voltage mode
CRM PFC controller does not need the rectified AC line voltage
information, it can save the power loss of the input voltage sens-
ing network that is necessary for the current mode CRM PFC
controller.
The FAN7528 provides the dual output voltage control function
without the AC line voltage sensing for adapter applications. It
changes the PFC output voltage according to the AC line volt-
age.
It provides many protection functions such as over voltage pro-
tection, open-feedback protection, over current protection and
under voltage lock out protection. The FAN7528 can be dis-
abled if the INV pin voltage is lower than 0.45V and then the
operating current decreases to 65uA. Using a new variable on-
time control method, THD is lower than the conventional CRM
boost PFC ICs.
Ordering Information
Part Number
FAN7528N
FAN7528M
FAN7528MX
Operating Temp.
Range
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
Pb-Free
Yes
Yes
Yes
Package
8-DIP
8-SOP
8-SOP
Packing Method
Rail
Rail
Tape & Reel
Marking
Code
FAN7528
FAN7528
FAN7528
©2005 Fairchild Semiconductor Corporation
1
FAN7528 Rev. 1.0.1
www.fairchildsemi.com