This part is a kind of semiconductor called 2SK1053.
Function of this product has N-Channel Silicon MOSFET.
Manufacturers : Sanyo Semicon Device
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Ordering number:EN3440 Features · Low ON-state resistance. · Ultrahigh-speed switching. N-Channel Silicon MOSFET 2SK1053 Ultrahigh-Speed Switching Applications Package Dimensions unit:mm 2052C [2SK1053] 10.2 3.6 5.1 4.5 1.3 2.7 6.3 15.1 18.0 5.6 1.2 0.8 123 Specifications Absolute Maximum Ratings at Ta = 25˚C Parameter Drain-to-Source Voltage Gate-to-Source Voltage Drain Current (DC) Drain Current (Pulse) Symbol VDSS VGSS ID IDP Allowable Power Dissipation PD Channel Temperature Storage Temperature Tch Tstg 2.55 Conditions PW≤10µs, duty cycle≤1% Tc=25°C Electrical Characteristics at Ta = 25˚C 2.55 Parameter Symbol Conditions Drain-to-Source Breakdown Voltage V(BR)DSS ID=1mA, VGS=0 Zero-Gate Voltage Drain Current IDSS VDS=450V, VGS=0 Gate-to-Source L [ ... ]