Fairchild intros high- and low-side SR controller

USA: As global energy regulations become more stringent, achieving higher efficiency in complex AC-DC designs – such as desktop PCs, servers and workstations – can be challenging. Typically, synchronous rectifier (SR) controllers are used to gain higher efficiency, but this method can result in high standby power consumption and design complexity.

To help designers meet strict energy regulations, Fairchild Semiconductor has developed the FAN6224 secondary-side synchronous rectifier (SR) controller to provide design flexibility and improve overall system efficiency.

The FAN6224 is the first SR high- and low-side controller device in Fairchild’s mWSaver technology series. Equipped with an internal, adjustable load-level Green Mode operation, the device stops all SR
switching operation and provides lower no-load power consumption.

Utilizing a linear-predict timing-control technique, the device employs a simple control method without current-sense circuitry for noise immunity, making it ideally suited for high- and low-side flyback converters in continuous or discontinuous conduction mode (CCM and DCM) and quasi-resonant (QR) systems.

For maximum design flexibility, the FAN6224 provides PWM frequency tracking and secondary-side winding voltage and is able to operate in both fixed- and variable-frequency systems up to 140kHz.