FSEZ1307: Primary-Side-Regulation PWM Controller with MOSFET Integrated

This third-generation Primary Side Regulation (PSR) PWM controller combination power MOSFET, FSEZ1307, provides several features to enhance the performance of low-power flyback converters. The proprietary topology, TRUECURRENT™, enables precise CC regulation and simplified circuit design for battery-charger applications. Compared to a conventional design or a linear transformer, a low-cost, smaller, and lighter charger results.

To minimize standby power consumption, the proprietary green mode provides off-time modulation to linearly decrease PWM frequency under light-load conditions. Green mode assists the power supply in meeting power conservation requirements.

By using the FSEZ1307, a charger can be implemented with few external components and minimized cost.

Features

• Low Standby Power: Under 30mW
• High-Voltage Startup
• Few External Components
• Constant-Voltage (CV) and Constant-Current (CC) Control without Secondary-Feedback Circuitry
• Green-Mode: Linearly Decreasing PWM Frequency
• Fixed PWM Frequency at 50kHz with Frequency Hopping to Solve EMI Problem
• Cable Compensation in CV Mode
• Peak-Current-Mode Control in CV Mode
• Cycle-by-Cycle Current Limiting
• V_DD Over-Voltage Protection with Auto Restart
• V_DD Under-Voltage Lockout (UVLO)
• Gate Output Maximum Voltage Clamped at 15V
• Fixed Over-Temperature Protection with Auto Restart
• Available in 7-Lead SOP Package

Application Notes