This part is a kind of semiconductor called FP6291.

Function of this product has 2.5A Step-Up Current Mode PWM Converter.

Manufacturers : Feeling Technology

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FP6291 1MHz, 2.5A Step-Up Current Mode PWM Converter General Description The FP6291 is a current mode boost DC-DC converter. Its PWM circuitry with built-in 0.2Ω power MOSFET make this regulator highly power efficient. The internal compensation network also minimizes as much as 6 external component counts. The non-inverting input of error amplifier connects to a 0.6V precision reference voltage and internal soft-start function can reduce the inrush current. The FP6291 is available in the SOT23-6L package and provides space-saving PCB for the application fields. Features  Adjustable Output up to 12V  Internal Fixed PWM frequency: 1.0MHz  Precision Feedback Reference Voltage: 0.6V (±2%)  Internal 0.2Ω, 2.5A, 16V Power MOSFET  Shutdown Current: 0.1μA  Over Temperature [ ... ]

FP6291 PDF Datasheet Download