SG6858 Datasheet | Fairchild Semiconductor

atures - Green-Mode PWM - Supports the ”Blue Angel” Standard - Low Startup Current: 10µA (Maximum) - Low Operating Current: 2.5m A - Leading-Edge Blanking (LEB) - Constant Output Power Limit - Built-in Synchronized Slope pensation - Current-Mode Operation - Cycle-by-Cycle Current Limiting - Under-Voltage Lockout (UVLO) - Programmable PWM Frequency - VDD Over-Voltage Protection with Auto-Restart - Gate Output Voltage Clamped at 17V - Few External ponents Required - SSOT-26 and DIP-8 Packages Available Applications - 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, PC 5V standby power, and consumer electronics - Replacements for linear transformers and RCC SMPS - Offline High Brightness (HB) LED drivers 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 greenmode function provides off-time modulation to linearly decrease the switching frequency under light-load conditions. This green-mode function enables the power supply to meet even the strictest power conservation requirements. The Bi CMOS fabrication process enables reducing the startup current to 10µA and the operating current to 2.5m A. To further improve power conservation, a large startup resistance can be used. Built-in synchronized slope pensation ensures the stability of peakcurrent-mode control. Proprietary internal pensation provides a constant output power limit over a universal AC input range (90VAC to 264VAC). Pulse-by-pulse current limiting ensures safe operation even during short circuits. To protect the external power MOSFET from being damaged by supply over voltage, the output driver is clamped at 17V. SG6858 controllers can improve...