This part is a kind of semiconductor called AP9918H.

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 :

AP9918H/J Advanced Power Electronics Corp. ▼ Low on-resistance ▼ Capable of 2.5V gate drive ▼ Low drive current ▼ Surface N-CHANNEL ENHANCEMENT MODE POWER MOSFET D BVDSS RDS(ON) ID 20V 14mΩ 45A mount package G S Description The Advanced Power MOSFETs from APEC provide the designer with the best combination of fast switching, ruggedized device design, ultra low on-resistance and cost-effectiveness. G D S TO-252(H) G D S TO-251(J) Absolute Maximum Ratings Symbol VDS VGS ID@TC=25℃ ID@TC=125℃ IDM PD@TC=25℃ TSTG TJ Parameter Drain-Source Voltage Gate-Source Voltage Continuous Drain Current, VGS @ 4.5V Continuous Drain Current, VGS @ 4.5V Pulsed Drain Current 1 Rating 20 ± 12 45 20 140 48 0.38 -55 to 150 -55 to 150 Units V V A A A W W/ ℃ ℃ �� [ ... ]

AP9918H PDF Datasheet Download