This part is a kind of semiconductor called K3455.
Function of this product has 2SK3455.
Manufacturers : NEC
Image and pinout :

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DATA SHEET MOS FIELD EFFECT TRANSISTOR 2SK3455 SWITCHING N-CHANNEL POWER MOS FET DESCRIPTION The 2SK3455 is N-channel DMOS FET device that features a low gate charge and excellent switching characteristics, designed for high voltage applications such as switching power supply, AC adapter. ORDERING INFORMATION PART NUMBER 2SK3455 PACKAGE Isolated TO-220 FEATURES •Low gate charge QG = 30 nC TYP. (VDD = 400 V, VGS = 10 V, ID = 12 A) •Gate voltage rating ±30 V •Low on-state resistance RDS(on) = 0.60 Ω MAX. (VGS = 10 V, ID = 6.0 A) •Avalanche capability ratings •Isolated TO-220 package ABSOLUTE MAXIMUM RATINGS (TA = 25°C) Drain to Source Voltage (VGS = 0 V) Gate to Source Voltage (VDS = 0 V) Drain Current (DC) (TC = 25°C) Drain Current (Pulse) Note1 VDSS VGSS ID(DC) ID(pul [ ... ]
K3455 PDF Datasheet Download
