April 2010
FAN7930
Critical Conduction Mode PFC Controller
Features
PFC Ready Signal
Input Voltage Absent Detection Circuit
Maximum Switching Frequency Limitation
Internal Soft-Start and Startup without Overshoot
Internal Total Harmonic Distortion (THD) Optimizer
Precise Adjustable Output Over-Voltage Protection
Open-Feedback Protection and Disable Function
Zero Current Detector
150μs Internal Startup Timer
MOSFET Over-Current Protection
Under-Voltage Lockout with 3.5V Hysteresis
Low Startup and Operating Current
Totem-Pole Output with High State Clamp
+500/-800mA Peak Gate Drive Current
8-Pin SOP
Applications
Adapter
Ballast
LCD TV, CRT TV
SMPS
Description
The FAN7930 is an active power factor correction (PFC)
controller for boost PFC applications that operate in
critical conduction mode (CRM). It uses a voltage-mode
PWM that compares an internal ramp signal with the
error amplifier output to generate a MOSFET turn-off
signal. Because the voltage-mode CRM PFC controller
does not need rectified AC line voltage information, it
saves the power loss of an input voltage sensing network
necessary for a current-mode CRM PFC controller.
FAN7930 provides over-voltage protection, open-
feedback protection, over-current protection, input-
voltage-absent detection, and under-voltage lockout
protection. The PFC-ready pin can be used to trigger
other power stages when PFC output voltage reaches
the proper level with hysteresis. The FAN7930 can be
disabled if the INV pin voltage is lower than 0.45V and
the operating current decreases to a very low level.
Using a new variable on-time control method, THD is
lower than the conventional CRM boost PFC ICs.
Related Resources
AN-8035 — Design Consideration for Boundary
Conduction Mode PFC Using FAN7930
Ordering Information
Part Number
Operating
Temperature
Range
FAN7930M
FAN7930MX
-40 to +125°C
Top Mark
Package
FAN7930 8-Lead Small Outline Package (SOP)
Packing
Method
Rail
Tape & Reel
© 2010 Fairchild Semiconductor Corporation
FAN7930 • Rev. 1.0.1
www.fairchildsemi.com