This part is a kind of semiconductor called K3405.

Function of this product has 2SK3405.

Manufacturers : NEC

Image and pinout :

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DATA SHEET MOS FIELD EFFECT TRANSISTOR 2SK3405 SWITCHING N-CHANNEL POWER MOS FET INDUSTRIAL USE DESCRIPTION The 2SK3405 is N-Channel MOS FET device that features a low on-state resistance and excellent switching characteristics, designed for low voltage high current applications such as DC/DC converter with synchronous rectifier. ORDERING INFORMATION PART NUMBER 2SK3405 2SK3405-ZK 2SK3405-ZJ PACKAGE TO-220AB TO-263(MP-25ZK) TO-263(MP-25ZJ) FEATURES • 4.5-V drive available • Low on-state resistance RDS(on)1 = 9.0 mΩ MAX. (VGS = 10 V, ID = 24 A) • Low gate charge QG = 34 nC TYP. (ID = 48 A, VDD = 16 V, VGS = 10 V) • Built-in gate protection diode • Surface mount device available ABSOLUTE MAXIMUM RATINGS (TA = 25°C ) Drain to Source Voltage (VGS = 0 V) Gate to Source Voltag [ ... ]

K3405 PDF Datasheet Download