This part is a kind of semiconductor called K3679-01MR.

Function of this product has 2SK3679-01MR.

Manufacturers : Fuji Electric

Image and pinout :

Some of the text within the PDF file :

2SK3679-01MR FUJI POWER MOSFET N-CHANNEL SILICON POWER MOSFET Outline Drawings [mm] TO-220F 200304 Super FAP-G Series Features High speed switching Low on-resistance No secondary breadown Low driving power Avalanche-proof Applications Switching regulators UPS (Uninterruptible Power Supply) DC-DC converters Maximum ratings and characteristicAbsolute maximum ratings (Tc=25°C unless otherwise specified) Ratings Unit V 900 V 900 Equivalent A Continuous drain current ±9 A Pulsed drain current ±36 V Gate-source voltage ±30 A Repetitive or non-repetitive 9 mJ Maximum Avalanche Energy 287.7 kV/µs Maximum Drain-Source dV/dt 40 Peak Diode Recovery dV/dt 5 kV/µs Gate(G) Max. power dissipation 2.16 W 95 Operating and storage Tch +150 °C -55 to +150 temperature range Tstg °C Isolation Voltag [ ... ]

K3679-01MR PDF Datasheet Download