The FSQ0170RNA, and FSQ0270RNA, consists of an integrated current mode Pulse Width Modulator (PWM) and an avalanche-rugged 700V Sense FET. It is specifically designed for high-performance off-line Switch Mode Power Supplies (SMPS) with minimal external components. The integrated PWM controller features include: a fixed-frequency generating oscillator, Under-Voltage Lockout (UVLO) protection, Leading Edge Blanking (LEB), an optimized gate turn-on/ turn-off driver, Thermal Shutdown (TSD) protection, and temperature compensated precision current sources for loop compensation and fault protection circuitry. Compared to a discrete MOSFET and controller or RCC switching converter solution, the FSQ0170RNA, and FSQ0270RNA reduces total component count, design size, and weight while increasing efficiency, productivity, and system reliability. These devices provide a basic platform that is well suited for the design of cost-effective flyback converters, as in PC auxiliary power supplies.