SG6859DZ

低成本绿色模式PWM控制器，用于反激式转换器 Low Cost Green-Mode PWM Controller for Flyback Converters

DESCRIPTION

This highly integrated PWM controller provides several special enhancements designed to meet the low standby-power needs of low-power SMPS. To minimize standby power consumption, the proprietary green-mode function provides off-time modulation to linearly decrease the switching frequency under light-load conditions. This green-mode function enables the power supply to easily meet even the strictest power conservation requirements.

FEATURES

■ Green-Mode PWM

■ Supports the “Blue Angel” Standard

■ Low Start-up Current 9uA

■ Low Operating Current 3mA

■ Leading-Edge Blanking

■ Constant Output Power Limit

■ Universal Input

■ Built-in Synchronized Slope Compensation

■ Current Mode Operation

■ Cycle-by-cycle Current Limiting

■ Under Voltage Lockout UVLO

■ Programmable PWM Frequency with Frequency Hopping

■ VDD Over Voltage Protection Auto Restart

■ Gate Output Voltage Clamped at 17V

■ Low Cost

■ Few External Components Required

■ Small SOT-26 and Dip 8 Packages

APPLICATIONS

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

■ Battery chargers for cellular phones, cordless phones, PDAs, digital cameras, and power tools

■ Power adapters for ink jet printers, video game consoles, and portable audio players

■ Open-frame SMPS for TV/DVD standby and other auxiliary supplies, home appliances, and consumer electronics

■ Replacements for linear transformers and RCC SMPS

■ PC 5V standby power.