Description
A Valley Switching Converter (VSC) generally shows lower EMI and higher power conversion efficiency than a conventional hard-switched converter with a fixed switching frequency. The FSQ510 is an integrated Valley Switching Pulse Width Modulation (VS-PWM) controller and SenseFET specifically designed for offline Switch-Mode Power Supplies (SMPS) for valley switching with minimal external components. The VSPWM controller includes an integrated oscillator, undervoltage lockout (UVLO), leading-edge blanking (LEB), optimized gate driver, internal soft-start, temperature-compensated precise current sources for loop compensation, and self-protection circuitry.

FEATUREs
◾ Uses an LDMOS Integrated Power Switch
◾ Optimized for Valley Switching Converter (VSC)
◾ Low EMI through Variable Frequency Control and
   Inherent Frequency Modulation
◾ High Efficiency through Minimum Drain Voltage
   Switching
◾ Extended Valley Switching for Wide Load Ranges
◾ Small Frequency Variation for Wide Load Ranges
◾ Advanced Burst-Mode Operation for Low Standby
   Power Consumption
◾ Pulse-by-Pulse Current Limit
◾ Protection Functions: Overload Protection (OLP),
   Internal Thermal Shutdown (TSD) with Hysteresis
◾ Under-Voltage Lockout (UVLO) with Hysteresis
◾ Internal Startup Circuit
◾ Internal High-Voltage SenseFET: 700 V
◾ Built-in Soft-Start: 5 ms

APPLICATIONs
◾ Auxiliary Power Supplies for LCD TV, LCD Monitor,
   Personal Computer, and White Goods