Description

A Valley Switching Converter 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 valley switching operation with minimal external components. The PWM controller includes an integrated fixed-frequency oscillator, Under-Voltage Lockout, Leading Edge Blanking (LEB), optimized gate driver, internal soft-start, temperature- compensated precise current sources for loop compensation, and self-protection circuitry.

Features

■ Optimized for Valley Switching (VSC)
■ Low EMI through Variable Frequency Control and ■nherent Frequency Modulation
■ 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
■ Pulse-by-Pulse Current Limit
■ Various Protection Functions: Overload Protection (OLP), Over-Voltage Protection (OVP), Abnormal Over-Current Protection (AOCP), Internal Thermal Shutdown (TSD)
■ Under-Voltage Lockout (UVLO) with Hysteresis
■ Internal Start-up Circuit
■ Internal High-Voltage SenseFET (650V)
■ Built-in Soft-Start (15ms)

Applications

■ Power Supply for DVP Player and DVD Recorder, Set-Top Box
■ Adapter
■ Auxiliary Power Supply for PC, LCD TV, and PDP TV