This part is a kind of semiconductor called TTK2837.

Function of this product has Silicon N Channel Field Effect Transistor.

Manufacturers : Toshiba

Image and pinout :

Some of the text within the PDF file :

TTK2837 TOSHIBA Field Effect Transistor Silicon N Channel MOS Type ( -MOS ) TTK2837 Switching Regulator Applications • Low drain-source on-resistance: RDS(ON) = 0.22 Ω (typ.) • High forward transfer admittance: |Yfs| = 8.5 S (typ.) • Low leakage current: IDSS = 10 µA (VDS = 500 V) • Enhancement mode: Vth = 1.5 to 3.0 V (VDS = 10 V, ID = 1 mA) Unit: mm 15.9 MAX. 3.2 ± 0.2 2.0 1.0 9.0 4.5 20.0 ± 0.3 3.3 MAX. 2.0 20.5 ± 0.5 Absolute Maximum Ratings (Ta = 25°C) Characteristics Drain-source voltage Gate-source voltage Drain current DC (Note 1) Pulse (t = 1 ms) (Note 1) Drain power dissipation (Tc = 25°C) Single pulse avalanche energy (Note 2) Avalanche current Repetitive avalanche energy (Note 3) Channel temperature Storage temperature range Symbol VDSS VGSS [ ... ]

TTK2837 PDF Datasheet Download