FAN6204A 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. FAN6204A 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 d e t e c t i o n , FA N 6 2 0 4 A c a n o p e r a t e i n b o t h f i x e d − a n d 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.