FSQ0765RQ — Green-Mode Farichild Power Switch (FPS™) for Quasi-Resonant Operation
April 2009
FSQ0765RQ Green-Mode Fairchild Power Switch (FPS™) for Quasi-Resonant Operation - Low EMI and High Efficiency
Features
! Optimized for Quasi-Resonant Converter (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 that is well suited 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 Operation for Low Standby ! Simple Scheme for Sync Voltage Detection ! Pulse-by-Pulse Current Limit ! Various Protection functions: Overload Protection
! ! ! !
(OLP), Over-Voltage Protection (OVP), Abnormal Over-Current Protection (AOCP), 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 L...
Q0765RQ PDF File
