This part is a kind of semiconductor called GS2678.

Function of this product has 5A 350KHz 25V Buck DC to DC Converter.

Manufacturers : SHENZHEN GSM ELECTAONIC

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Datasheet 5A 350KHz 25V Buck DC to DC Converter Features „ „ „ „ General Description The GS2678 is a 350 KHz fixed frequency PWM buck (step-down) DC/DC converter, capable of driving a 5A load with high efficiency, low ripple and excellent line and load regulation. Requiring a minimum number of external components, the regulator is simple to use and include internal frequency compensation and a fixed-frequency oscillator. The PWM control circuit is able to adjust the duty ratio linearly from 0 to 100%. An enable function, an over current protection function is built inside. When short protection function happens, the operation frequency will be reduced from 350KHz to 80KHz. An internal compensation block is built in to minimize external component count. Wide 3.6V to 25V Input Voltage [ ... ]

GS2678 PDF Datasheet Download