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is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.FAN400A Low-Power Green-Mode PWM Flyback Power Controller without Secondary Feedback
FAN400A Low-Power Green-Mode PWM Flyback Power
Controller without Secondary Feedback
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 Voltage (CV) and Constant Current (CC)
switching frequency under light-load and zero-load
No Secondary Feedback
conditions. This green mode enables the power supply
Low Startup Current: 8 A to meet international power conservation requirements.
The supply voltage V is also used for feedback
DD
Low Operating Current: 3.6mA
compensation, to regulate the output voltage without
Leading-Edge Blanking
requiring a conventional TL431 and a photo-coupler.
Another advantage of the FAN400A is that the typical
Constant Power Limit
startup current is only 8 A, while the typical operating
Universal AC Input Range
current can be as low as 3.6mA. A large startup
resistance can be used to achieve even higher power
Synchronized Slope Compensation
conversion efficiency.
140 C OTP Sensor with Hysteresis
FAN400A integrates a frequency hopping function
V Over-Voltage Clamping
DD
internally to reduce EMI emissions with minimum line
Cycle-by-Cycle Current Limiting
filters. Built-in synchronized slope compensation
maintains the stability of peak current-mode control.
Under-Voltage Lockout (UVLO)
Proprietary internal compensation ensures constant
Fixed PWM Frequency with Hopping
output power limiting over a universal range of AC input
voltages, from 90V to 264V .
AC AC
Gate Output Maximum Voltage Clamped at 17V
Small SSOT-6 Package The FAN400A provides many protection functions.
Pulse-by-pulse current limiting ensures constant output
current, even if a short circuit occurs. The internal
Applications
protection circuit disables PWM output if V exceeds
DD
22.7V. The gate output is clamped at 17V to protect the
General-purpose, switching mode, power supplies and
power MOS from over-voltage damage. The built-in
flyback power converters, such as:
over-temperature protection (OTP) function shuts down
Battery Chargers for Cellular Phones, Cordless
the controller at 140 C with a 30 C hysteresis.
Phones, PDAs, Digital Cameras, Power Tools
The FAN400A is designed to provide a low-cost total
Power Adapters for Ink Jet Printers, Video Game
solution for flyback converters. It is available in a small-
Consoles, Portable Audio Players
footprint, 6-pin, SSOT-6 package.
Open-Frame SMPS for TV/DVD Standby and
Auxiliary Supplies, Home Appliances, Consumer
Electronics Related Resources
Replacement for Linear Transformers and RCC SMPS
AN-400A Low-Power Green-Mode PWM Flyback
PC 5V Standby Power
Power Controller without Secondary Feedback
Ordering Information
Part Number Operating Temperature Range Package Packing Method
Eco Status
FAN400ATY SSOT-6 Green Tape & Reel
-40 C to +105 C
FAN400ANY -40 C to +105 C DIP-8 Green Tube
2008 Fairchild Semiconductor Corporation www.fairchildsemi.com
FAN400A Rev. 2, Feb-2020