FSQ0565RQ

FSQ0565RS/RQ — Green-Mode Farichild Power Switch (FPS™) for Quasi-Resonant Operation December 2009 FSQ0565RS/RQ Green-Mode Fairchild Power Switch (FPS™) for Quasi-Resonant Operation - Low EMI and High Efficiency Features ! Optimized for Quasi-Resonant Converters (QRC) ! Low EMI through Variable Frequency Control and AVS Description A Quasi-Resonant Converter (QRC) generally shows lower EMI and higher power conversion efficiency than a conventional hard-switched converter with a fixed switching frequency. The FSQ-series is an integrated Pulse-Width Modulation (PWM) controller and SenseFET specifically designed for quasi-resonant operation and Alternating Valley Switching (AVS). The PWM controller includes an integrated fixed-frequency oscillator, Under-Voltage Lockout (UVLO), LeadingEdge Blanking (LEB), optimized gate driver, internal softstart, temperature-compensated precise current sources for a loop compensation, and self-protection circuitry. Compared with a discrete MOSFET and PWM controller solution, the FSQ-series can reduce total cost, component count, size, and weight; while simultaneously increasing efficiency, productivity, and system reliability. This device provides a basic platform for cost-effective designs of quasi-resonant switching flyback converters. (Alternating Valley Switching) ! High-Efficiency through Minimum Voltage Switching ! Narrow Frequency Variation Range over Wide Load and Input Voltage Variation Power Consumption ! Advanced Burst-Mode Op...