This part is a kind of semiconductor called SG5841J.

Function of this product has Highly Integrated Green-Mode PWM Controller.

Manufacturers : Fairchild Semiconductor

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Product Specification Highly Integrated Green-Mode PWM Controller SG5841/J DESCRIPTION The highly integrated SG5841/J series of PWM controllers provides several features to enhance the performance of flyback converters. To minimize standby power consumption, a proprietary green-mode function provides off-time modulation to continuously decrease the switching frequency at light-load conditions. This green-mode function enables the power supply to meet international power conservation requirements. To further reduce power consumption, SG5841/J is manufactured using the BiCMOS process. This allows a low start-up current, around 14µA, and an operating current of only 4mA. As a result, a large start-up resistance can be used. The SG5841/J built-in synchronized slope compensation achieves stab [ ... ]

SG5841J PDF Datasheet Download