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 meet even the strictest power conservation requirements.

The BiCMOS fabrication process enables reducing the start-up current to 10µA and the operating current to 2.5mA. To further improve power conservation, a large start-up resistance can be used. Built-in synchronized slope compensation ensures the stability of peak current mode control. Proprietary internal compensation provides a constant output power limit over a universal AC input range (90V_AC to 264V_AC). 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 events, the SG6858’s output driver is clamped at 17V. SG6858 controllers can be used to improve the performance and reduce the production cost of power supplies and can replace linear and RCC-mode power adapters. It is available in 8-pin DIP and 6-pin SSOT-26 packages.

• Green-Mode PWM
• Supports the "Blue Angel" Standard
• Low Startup Current: 10µA (Maximum)
• Low Operating Current: 2.5mA
• Leading-Edge Blanking (LEB)
• Constant Output Power Limit
• Built-in Synchronized Slope Compensation
• Current-Mode Operation
• Cycle-by-Cycle Current Limiting
• Under-Voltage Lockout (UVLO)
• Programmable PWM Frequency
• V_DD Over-Voltage Protection with Auto-Restart
• Gate Output Voltage Clamped at 17V
• Few External Components Required
• SSOT-26 and DIP-8 Packages Available

• 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