This part is a kind of semiconductor called AP9T18GH-HF-3.

Function of this product has N-channel Enhancement-mode Power MOSFET.

Manufacturers : Advanced Power Electronics

Image and pinout :

Some of the text within the PDF file :

Advanced Power Electronics Corp. AP9T18GH/J-HF-3 N-channel Enhancement-mode Power MOSFET Supports Gate Drive as low as 2.5V Fast Switching Characteristics Low Gate Charge RoHS-compliant, Halogen-free G S D BV DSS R DS(ON) ID 20V 14mΩ 38A Description Advanced Power MOSFETs from APEC provide the designer with the best combination of fast switching, low on-resistance and cost-effectiveness. G D S TO-252 (H) The AP9T18GH-HF-3 is in the TO-252 package which is widely preferred for commercial and industrial surface mount applications such as medium-power DC/DC converters. The through-hole TO-251 version (AP9T18GJ-HF-3) is available where a small PCB footprint is required. G D S TO-251 (J) Absolute Maximum Ratings Symbol VDS VGS ID at TC=25°C ID at TC=100°C IDM PD at TC=25°C TSTG TJ [ ... ]

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