This part is a kind of semiconductor called TD1583.
Function of this product has 3A 380Khz 28V PWM Buck DC/DC Converter.
Manufacturers : Techcode
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Datasheet 3A 380KHZ 28V PWM Buck DC/DC Converter TD1583 General Description The TD1583 is a 380 KHz fixed frequency monolithic step down switch mode regulator with a built in internal Power MOSFET. It achieves 3A continuous output current over a wide input supply range with excellent load and line regulation. The device includes a voltage reference, oscillation circuit, error amplifier, internal PMOS and etc. The PWM control circuit is able to adjust the duty ratio linearly from 0 to 100%. An enable function, an over current protection function and a short circuit protection function are built inside. An internal compensation block is built in to minimize external component count. The TD1583 serves as ideal power supply units for portable devices. Features [ ... ]