FAN400C Low-Power, Green-Mode, PWM Flyback Power Controller without Secondary Feedback (CC)
October 2008
FAN400C Low-Power, Green-Mode, PWM Flyback Power
Controller without Secondary Feedback (CC)
Features Description
This highly integrated PWM controller provides several
Linearly Decreasing PWM Frequency
features to enhance the performance of low-power
Green Mode Under Light-Load and Zero-Load
flyback converters. To minimize standby power
Conditions
consumption, a proprietary green-mode function
provides off-time modulation to linearly decrease the
Constant Current (CC) without Secondary-Feedback
switching frequency under light-load and zero-load
Circuitry
conditions. This green mode enables the power supply
Low Startup Current: 8 A
to meet international power conservation requirements.
Low Operating Current: 3.6mA
Another advantage of the FAN400C is that the typical
startup current is only 8 A, while the typical operating
Leading-Edge Blanking
current can be as low as 3.6mA. A large startup
Constant Power Limit
resistance can be used to achieve higher power
conversion efficiency.
Universal AC Input Range
FAN400C integrates a frequency-hopping function
Synchronized Slope Compensation
internally to reduce EMI emissions with minimum line
140 C OTP Sensor with Hysteresis
filters. Built-in synchronized slope compensation
V Over-Voltage Protection (Auto Restart) maintains the stability of peak current-mode control.
DD
Proprietary internal compensation ensures constant
Cycle-by-Cycle Current Limiting
output power limiting over a universal range of AC input
Under-Voltage Lockout (UVLO)
voltages, from 90V to 264V .
AC AC
Fixed PWM Frequency with Hopping
The FAN400C provides many protection functions.
Pulse-by-pulse current limiting ensures constant output
Gate Output Maximum Voltage Clamped at 17V
current, even if a short circuit occurs. The internal
Small SSOT-6 Package
protection circuit disables PWM output if V exceeds
DD
24.5V. The gate output is clamped at 17V to protect the
Applications
power MOS from over-voltage damage. The built-in
over-temperature protection (OTP) function shuts down
General-purpose, switching-mode power supplies and
the controller at 140 C with a 30 C hysteresis.
flyback power converters, such as:
The FAN400C is designed to provide a low-cost total
Battery Chargers for Cellular Phones, Cordless
solution for flyback converters. It is available in a small
Phones, PDAs, Digital Cameras, Power Tools
footprint, 6-pin, SSOT-6 and 8-pin DIP packages.
Power Adapters for Ink Jet Printers, Video Game
Consoles, Portable Audio Players
Related Resources
Open-Frame SMPS for TV/DVD Standby and
Auxiliary Supplies, Home Appliances, Consumer
AN-6072 Low-Power, Green-Mode, PWM Flyback
Electronics
Power Controller without Secondary Feedback
Replacement for Linear Transformers and RCC SMPS
PC 5V Standby Power
Ordering Information
Part Number Operating Temperature Range Package Packing Method
Eco Status
FAN400CTY -40 C to +105 C SSOT-6 Green Tape & Reel
FAN400CNY DIP-8 Green Tube
-40 C to +105 C
For Fairchilds definition of green please visit: FAN400C Low-Power, Green-Mode, PWM Flyback Power Controller without Secondary Feedback (CC)
Application Diagram
Figure 1. Typical Application
Internal Block Diagram
Figure 2. Functional Block Diagram
2008 Fairchild Semiconductor Corporation www.fairchildsemi.com
FAN400C Rev. 1.0.2 2