This part is a kind of semiconductor called FR3709Z.

Function of this product has IRFR3709Z.

Manufacturers : International Rectifier

Image and pinout :

Some of the text within the PDF file :

Applications l High Frequency Synchronous Buck Converters for Computer Processor Power l High Frequency Isolated DC-DC Converters with Synchronous Rectification for Telecom and Industrial Use Benefits l Very Low RDS(on) at 4.5V VGS l Ultra-Low Gate Impedance l Fully Characterized Avalanche Voltage and Current PD - 94712 IRFR3709Z IRFU3709Z HEXFET® Power MOSFET VDSS RDS(on) max Qg 30V 6.5m: 17nC D-Pak IRFR3709Z I-Pak IRFU3709Z Absolute Maximum Ratings Parameter VDS Drain-to-Source Voltage VGS ID @ TC = 25°C ID @ TC = 100°C IDM PD @TC = 25°C PD @TC = 100°C Gate-to-Source Voltage Continuous Drain Current, VGS @ 10V ™Continuous Drain Current, VGS @ 10V Pulsed Drain Current Maximum Power Dissipation Maximum Power Dissipation TJ TSTG Linear Derating Factor Operating Junction and S [ ... ]

FR3709Z PDF Datasheet Download