Description

This highly integrated PWM controller provides several features to enhance the performance of low-power flyback converters. To minimize standby power consumption, a proprietary green-mode function provides off-time modulation to linearly decrease the switching frequency under light-load and zero-load conditions. This green mode enables the power supply to meet international power conservation requirements. Another advantage of the FAN400C is that the typical startup current is only 8μA, while the typical operating current can be as low as 3.6mA. A large startup resistance can be used to achieve higher power conversion efficiency.

Features

■ Linearly Decreasing PWM Frequency

■ Green Mode Under Light-Load and Zero-Load Conditions

■ Constant Current (CC) without Secondary-Feedback Circuitry

■ Low Startup Current: 8μA

■ Low Operating Current: 3.6mA

■ Leading-Edge Blanking

■ Constant Power Limit

■ Universal AC Input Range

■ Synchronized Slope Compensation

■ 140°C OTP Sensor with Hysteresis

■ VDD Over-Voltage Protection (Auto Restart)

■ Cycle-by-Cycle Current Limiting

■ Under-Voltage Lockout (UVLO)

■ Fixed PWM Frequency with Hopping

■ Gate Output Maximum Voltage Clamped at 17V

■ Small SSOT-6 Package

Applications

General-purpose, switching-mode, power supplies and flyback power converters, such as:

■ Battery Chargers for Cellular Phones, Cordless Phones, PDAs, Digital Cameras, Power Tools

■ Power Adapters for Ink Jet Printers, Video Game Consoles, Portable Audio Players

■ Open-Frame SMPS for TV/DVD Standby and Auxiliary Supplies, Home Appliances, Consumer Electronics

■ Replacement for Linear Transformers and RCC SMPS

■ PC 5V Standby Power