FSQ211: 650V Integrated Power Switch for 8Watt offline flyback converters

The FSQ211 consists of an integrated Pulse Width Modulator (PWM) and SenseFET, specifically designed for high-performance, off-line Switch Mode Power Supplies (SMPS) with minimal external components. This device is an integrated high-voltage power switching regulator that combines a VDMOS SenseFET with a voltage mode PWM control block. The integrated PWM controller features include a fixed 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. When compared to a discrete MOSFET and controller or RCC switching converter solution, the FSQ211 device reduces total component count and design size and weight, while increasing efficiency, productivity, and system reliability. This device provides a basic platform well suited for cost-effective flyback converters.

Features

• Internal Avalanche-Rugged SenseFET
• Precision Fixed Operating Frequency (67KHz)
• Burst-Mode Operation
• Internal Start-up Circuit
• Pulse-by-Pulse Current Limiting
• Overload Protection (OLP)
• Internal Thermal Shutdown Function (TSD)
• Auto-Restart Mode
• Under-Voltage Lockout (UVLO) with Hysteresis
• Built-in Soft Start (15ms)
• Secondary-Side Regulation

Application Notes