This part is a kind of semiconductor called ETA9640E8A.

Function of this product has 5V/1A Synchronous Boost.

Manufacturers : ETA

Image and pinout :

Some of the text within the PDF file :

ETA9640 5V/1A Synchronous Boost with 1A Linear Charger for Power Bank DESCRIPTION The ETA9640 is a fully integrated power management unit specifically designed for Power Bank, Mobile Charger, Backup Battery Charger applications. It consists of a high efficiency synchronous step-up boost converter and a linear battery charger. The boost can provide up to 1A output current at 5V of from a Li-Ion battery input voltage, while the charger can charge up to 1A of current from an AC adapter input. The boost incorporates circuits that disconnect the input from output, during shutdown, short-circuit, output current overloading, or other events when output is higher than the input. This not only eliminates the need for an external MOSFET and its control circuitry to disconnect the input from output, [ ... ]

ETA9640E8A PDF Datasheet Download