●Green-Mode Fairchild Power Switch (FPS™) for Quasi-Resonant Operation- Low EMI and High Efficiency
●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), Leading Edge Blanking (LEB), optimized gate driver, internal soft start, 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.
●Features
●Optimized for Quasi-Resonant Converters (QRC)
●Low EMI through Variable Frequency Control and AVS (Alternating Valley Switching)
●High-Efficiency through Minimum Voltage Switching
●Narrow Frequency Variation Range over Wide Load and Input Voltage Variation
●Advanced Burst-Mode Operation for Low Standby Power Consumption
●Simple Scheme for Sync Voltage Detection
●Pulse-by-Pulse Current Limit
●Various Protection Functions: Overload Protection (OLP), Over-Voltage Protection (OVP), Internal
●Thermal Shutdown (TSD) with Hysteresis, Output Short Protection (OSP)
●Under-Voltage Lockout (UVLO) with Hysteresis
●Internal Startup Circuit
●Internal High-Voltage Sense FET (650V)
●Built-in Soft-Start (17.5ms)
●Applications
●Power Supply for LCD TV and Monitor, VCR, SVR, STB, and DVD & DVD Recorder
●Adapter
