This part is a kind of semiconductor called FP6381A.

Function of this product has High Efficiency 1.5MHz 1.2A Synchronous Step Down Regulator.

Manufacturers : Fiti

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fitipower integrated technology lnc. FP6381A High Efficiency 1.5MHz/a18.52AT Synchronous Step Down Regulator Description The FP6381A is a high efficiency, high frequency synchronous DC-DC step-down converter. The 100% duty cycle feature provides low dropout operation, extending battery life in portable systems. The internal synchronous switch increases efficiency and eliminates the need for external Schottky diode. At shutdown mode, the input supply current is less than 1µA. The current limit protection and on-chip thermal shutdown features provide protection against any combination of overload or ambient temperature. Pin Assignments S5 Package (SOT-23-5) FB VIN 54 1 23 EN GND LX S6 Package (SOT-23-6) FB PG VIN 6 54 1 23 EN GND LX S8 Package (TSOT-23-5) FB VIN 54 1 23 Features [ ... ]

FP6381A PDF Datasheet Download