Fairchild Fan6755W Data Handbook

6755W / F 6755U aver™ tro ller

June 2011

FAN6755W / FAN6755UW m WSaver™ PWM Controller Features Description

 m WSaver™ Technology Provides Industry’s Best-in- This highly integrated PWM controller provides several features to enhance the performance of flyback

Class Standby Power

converters.

o <100m W at 25m W Load for LCDM Adaptor

To minimize standby power consumption, a proprietary

o Internal High-Voltage JFET Startup

adaptive green-mode function reduces switching

o Low Operating Current Maximum: 2m A

frequency at light-load condition. To avoid acoustic-

o Adaptive Decreasing of PWM Frequency to noise problems, the minimum PWM frequency is set 23KHz at Light-Load Condition, Improved above 23k Hz. This green-mode function enables the Light-Load Efficiency power supply to meet international power conservation

o Feedback Impedance Switching During requirements, such as Energy Star®. With the internal Minimum Load or No Load high-voltage startup circuitry, the power loss caused by bleeding resistors is also eliminated. To further reduce

 Proprietary Asynchronous Frequency Hopping

power consumption, FAN6755W/UW uses the Bi CMOS

Reduced EMI

process, which allows an operating current of only 2m A.  Fixed PWM Frequency: 65KHz (FAN6755W), The standby power consumption can be under 100m W 130KHz (FAN6755UW) for most of LCD monitor power supply designs.

 Internal Leading-Edge Blanking FAN6755W/UW integrates a frequency-hopping function

that reduces EMI emission of a power supply with

 Built-in Synchronized Slope Compensation

minimum line filters. Its built-in synchronized slope  Auto-Restart Protection: Feedback Open-Loop compensation achieves a stable peak-current-mode Protection (OLP), VDD Over-Voltage Protection control and improves noise immunity. The proprietary, (OVP), Over-Temperature Protection (OTP), and external line compensation ensures constant output Line Over-Voltage Protection power limit over a wide AC input voltage range from 90VAC to 264VAC.

 Soft Gate Drive with Clamped Output Voltage: 18V

FAN6755W/UW provides many protection functions.

 VDD Under-Voltage Lockout (UVLO)

The internal feedback open-loop protection circuit  Programmable Constant Power Limit (Full AC protects the power supply from open feedback loop Input Range) condition or output short condition. It also has line under-voltage protection (brownout protection) and over-

 Internal OTP Sensor with Hysteresis

voltage protection using an input voltage sensing pin

 Build-in 5ms Soft-Start Function (VIN).  Input Voltage Sensing (VIN Pin) for Brown-In/Out

FAN6755W/UW is available in a 7-pin SOP package.

Protection with Hysteresis and Line Over-Voltage Protection

Applications General-purpose switched-mode power supplies and flyback power converters, including:  LCD Monitor Power Supply  Open-Frame SMPS

ENERGY STAR® is a registered trademark of the U.S. Department of Energy and the U.S. Environmental Protection Agency.

© 2009 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN6755W / FAN6755UW • Rev. 1.0.5