FSQ0565RQ

650V Integrated Power Switch with Quasi-Resonant Operation for 60W offline flyback converters

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

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Optimized for Quasi-Resonant Converter QRC

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Low EMI through Variable Frequency Control and AVSAlternating Valley Switching

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High-Efficiency through Minimum Voltage Switching

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Narrow Frequency Variation Range over Wide Loadand Input Voltage Variation

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Advanced Burst-Mode Operation for Low StandbyPower Consumption

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Simple Scheme for Sync Voltage Detection

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Pulse-by-Pulse Current Limit

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Various Protection functions: Overload ProtectionOLP, Over-Voltage Protection OVP, Internal ThermalShutdown TSD with Hysteresis, Output ShortProtection OSP

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Under-Voltage Lockout UVLO with Hysteresis

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Internal Startup Circuit

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Internal High-Voltage Sense FET 650V

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Built-in Soft-Start 17.5ms