This part is a kind of semiconductor called AOZ1052PI.

Function of this product has 4A Synchronous Buck Regulator.

Manufacturers : Alpha & Omega Semiconductors

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EZBuck™ 4A Synchronous Buck Regulator AOZ1052PI General Description The AOZ1052PI is a high efficiency, easy to use, 4A synchronous buck regulator. The AOZ1052PI works from 4.5V to 18V input voltage range, and provides up to 4A of continuous output current with an output voltage adjustable down to 0.8V. The AOZ1052PI comes in an exposed pad SO-8 package and is rated over a -40°C to +85°C operating ambient temperature range. Features  4.5V to 18V operating input voltage range  Synchronous Buck: 60mΩ internal high-side switch and 20mΩ internal low-side switch (at 12V)  Up to 95% efficiency  External soft start  Output voltage adjustable to 0.8V  4A continuous output current  450kHz PWM operation  Cycle-by-cycle current limit  Pre-bias start-up  Short [ ... ]

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