This part is a kind of semiconductor called SD6109.

Function of this product has VOLTAGE MODE PWM POWER SUPPLY.

Manufacturers : Silan Microelectronics Joint-stock

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SD6109 VOLTAGE MODE PWM POWER SUPPLY WITH BUILT-IN SUPERVISOR, PROTECTION AND REGULATION FOR PCs DESCRIPTION The SD6109 is a power management IC for computers. It integrates various monitoring functions and protections, such as AC fail detection, over power protection, negative voltage protection, over/under voltage protection and provides power down signal for PG. Built-in high precision oscillator provides accurate protection and delay time for monitoring. And internal regulators TL431 are used for stable output 3.3V and 5V, with few peripheral components. Built-in soft-start decreases stress of transformer against saturation. SD6109 used for pull-push or half-bridge power system with high efficiency and stability. DIP-20-300-2.54 FEATURES * Advanced Bi-CMOS proces [ ... ]

SD6109 PDF Datasheet Download