FAN6204 − mWSaver™ Synchronous Rectification Controller for Flyback and Forward Freewheeling Rectification


FAN6204 is a secondary-side synchronous rectification (SR) controller to drive SR MOSFET for improving efficiency. The IC is suitable for flyback converters and forward free-wheeling rectification.

FAN6204 can be applied in continuous or discontinuous conduction mode (CCM and DCM) and quasi-resonant (QR) flyback converters based on the proprietary innovative linear-predict timing-control technique. The benefits of this technique include a simple control method without current-sense circuitry to accomplish noise immunity.

With PWM frequency tracking and secondary-side winding voltage detection, FAN6204 can operate in both fixed- and variable-frequency systems.

In Green Mode, the SR controller stops all SR switching operation to reduce the operating current. Power consumption is maintained at minimum level in light-load condition.

Download Datasheet Buy Products Request Free Samples Product Availability

Product Status/Pricing/Packaging

Product Product & Eco Status *Pricing Packaging & Packing Info **Package Marking Convention Qualification Support Compliance Certificates
0 FAN6204MY Full Production
Green as of Mar 2010
$0.58  Details

Line 1:$Y (Fairchild logo)
&Z (Plant Code)
&2 (2-Digit Date Code) &K
Line 2:6204
Line 3:MYB
FIT :  1  
ESD (CDM) :  2000  V
ESD (HBM) :  5000  V
Show more...


  • mWSaver™ Technology:
  • Internal Green Mode to Stop SR Switching for Lower No-Load Power Consumption
  • 1.1mA Ultra-Low Green Mode Operating Current
  • SR Controller
  • Suited for Flyback Converter in QR, DCM, and CCM Operation
  • Suited for Forward Freewheeling Rectification
  • PWM Frequency Tracking with Secondary-Side Winding Voltage Detection
  • Ultra-Low VDD Operating Voltage for Various Output Voltage Applications (5V~24V)
  • VDD Pin Over-Voltage Protection (OVP)
  • 12V (Typical) Gate Driver Clamp
  • 8-Pin SOP Package


  • Notebook PC
  • Server
  • Workstation
  • LCD TV
  • Other Consumer Products

Application Notes

Technical Articles

Reference Designs

Application Document Number Featured Products Output
SMPS NB Adapter RD-351 FAN6204, FAN6920MR, FAN7382 90W 90~264V AC Dual Switch Flyback
SMPS AIO PC Power RD-352 FAN6204, FAN6920MR, FAN7382 120W 90~264V AC Dual Switch Flyback
SMPS AIO PC Power RD-353 FAN6204, FAN6920MR, FAN7382 120W 90~264V AC Dual Switch Flyback

Online Seminar

A High Power Factor Flyback with Constant-Current Output for LED Lighting Applications
This article explains the principles of AC/DC converters in flyback topology having a high power factor input and a constant current output. The most commonly used mode of operation for this purpose is boundary conduction mode (BCM). The basics of this mode are developed and its drawbacks are made clear. A simple method for improving power factor is introduced and explained in detail. Operating in DCM mode improves power factor and THD while reducing the peak drain voltage. A quick design example is given and the special issues of driving high power LEDs are explained.
PDF White Paper

© Copyright Fairchild Semiconductor. All rights reserved. Privacy Policy | Site Terms & Conditions | Standard Terms & Conditions of Sale | Trademarks | Site Map | IPC Saving our world 1mW at a time
  Knowledge Base Support Request Form.
  Slide to enable Submit button:
Locked Unlocked