This part is a kind of semiconductor called FDZ1416NZ.

Function of this product has MOSFET.

Manufacturers : Fairchild Semiconductor

Image and pinout :

Some of the text within the PDF file :

FDZ1416NZ Common Drain N-Channel 2.5 V PowerTrench® WL-CSP MOSFET June 2015 FDZ1416NZ Common Drain N-Channel 2.5 V PowerTrench® WL-CSP MOSFET 24 V, 7 A, 23 m Features  Max rS1S2(on) = 23 m at VGS = 4.5 V, IS1S2 = 1 A  Max rS1S2(on) = 25 m at VGS = 4 V, IS1S2 = 1 A  Max rS1S2(on) = 28 m at VGS = 3.1 V, IS1S2 = 1 A  Max rS1S2(on) = 33 m at VGS = 2.5 V, IS1S2 = 1 A  Occupies only 2.2 mm2 of PCB area  Ultra-thin package: less than 0.35 mm height when mounted to PCB  High power and current handling capability  HBM ESD protection level > 3.2 kV (Note 3)  RoHS Compliant General Description This device is designed specifically as a single package solution for Li-Ion battery pack protection circuit and other ultra-portable applications. It features tw [ ... ]

FDZ1416NZ PDF Datasheet Download