The FSCQ1565RTYDTU is a 650V Integrated Power Switch for 170W offline flyback converters. A Quasi-Resonant Converter (QRC) typically shows lower EMI and higher power conversion efficiency compared to a conventional hard-switched converter with a fixed switching frequency. Therefore, a QRC is well suited for noise-sensitive applications, such as colour TV and audio. Each product in the FSCQ series contains an integrated Pulse Width Modulation (PWM) controller and a SenseFET. This series is specifically designed for quasi-resonant off-line Switch Mode Power Supplies (SMPS) 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.