This part is a kind of semiconductor called B6020S.
Function of this product has Dual N-Channel 60-V (D-S) MOSFET.
Manufacturers : BiTEK
Image and pinout :

Some of the text within the PDF file :
B6020S Dual N-Channel 60-V (D-S) MOSFET General Description The B6020S is the Dual N-Channel logic enhancement mode power field effect transistors to provide excellent RDS(on), low gate charge and low gate resistance. It’s up to 60V operation voltage is well suited in switching mode power supply, SMPS, notebook computer power management and other battery powered circuits. Pin Configuration Features RDS(ON)=90mΩ@VGS=10V (N-Ch) RDS(ON)=120mΩ@VGS=4.5V (N-Ch) Super high density cell design for extremely low RDS(ON) Exceptional on-resistance and maximum DC current SOP-8 Package Applications Switching power supply, SMPS Battery Powered System DC/DC Converter DC/AC Converter Load Switch ℃Absolute Maximum Ratings (TA=25 Unless Otherwise Noted): Parameter Drain-Source Voltage Gate-Sou [ ... ]
B6020S PDF Datasheet Download
