Description
The FSDx321(x stands for H, L) are integrated Pulse Width Modulators (PWM) and Sense FETs specifically designed for high performance offline Switch Mode Power Supplies (SMPS) with minimal external components. Both devices are integrated high voltage power switching regulators which combine an avalanche rugged Sense FET with a current mode PWM control block.

Features
• Internal Avalanche Rugged Sense FET
• Consumes only 0.65W at 240VAC & 0.3W load with Advanced Burst-Mode Operation
• Frequency Modulation for low EMI
• Precision Fixed Operating Frequency
• Internal Start-up Circuit
• Pulse by Pulse Current Limiting
• Abnormal Over Current Protection
• Over Voltage Protection
• Over Load Protection
• Internal Thermal Shutdown Function
• Auto-Restart Mode
• Under Voltage Lockout
• Low Operating Current (max 3mA)
• Adjustable Peak Current Limit
• Built-in Soft Start

Applications
• SMPS for STB, Low cost DVD
• Auxiliary Power for PC
• Adaptor for Charger