SG6858 − Low Cost Green-Mode PWM Controller for Flyback Converters


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 (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 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.

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Product Status/Pricing/Packaging

Product Product & Eco Status *Pricing Packaging & Packing Info **Package Marking Convention Qualification Support Compliance Certificates
0 SG6858TZ Not recommended for new design
Green as of Jul 2011
$0.22  Details
0.97 x 4.22 x 1.6mm

Line 1:&E (Space)
&E (Space)
&Y (Binary Calendar Year Coding)
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FIT :  1  
ESD (HBM) :  3000  V
RƟJA :  82.5  °C/W
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0 SG6858DZ Not recommended for new design
Green as of Aug 2012
N/A  Details

Line 1:SG6858DZ
Line 2:B3&6&3 (3-Digit Date Code)
&Z (Plant Code)
FIT :  1  
ESD (HBM) :  3000  V
RƟJA :  82.5  °C/W


  • 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
  • VDD Over-Voltage Protection with Auto-Restart
  • Gate Output Voltage Clamped at 17V
  • Few External Components Required
  • SSOT-26 and DIP-8 Packages Available


  • Notebook PC
  • Wireless LAN Access Point/Router
  • External AC-DC Merchant Power Supply - Wireless Communications
  • DVD
  • STB

Application Notes

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