This part is a kind of semiconductor called BD743.

Function of this product has Silicon NPN Power Transistors.

Manufacturers : Comset Semiconductors

Image and pinout :

Some of the text within the PDF file :

SEMICONDUCTORS BD743 – A – B – C SILICON POWER TRANSISTORS The BD743 series are NPN power transistors in a TO-220 envelope. They are intended for use in power linear and switching application. High current capability and high power dissipation. PNP complements are BD744-A-B-C Compliance to RoHS. ABSOLUTE MAXIMUM RATINGS Symbol Ratings BD743 BD743A BD743B BD743C BD743 BD743A BD743B BD743C BD743 BD743A BD743B BD743C BD743 BD743A BD743B BD743C BD743 BD743A BD743B BD743C BD743 BD743A BD743B BD743C TC = 25°C TA = 25°C Value 50 70 900 110 45 60 80 100 5 Unit VCBO Collector-Base Voltage (IE=0) V www.DataSheet.net/ VCEO Collector-Emitter Voltage (IB=0) V VEBO Emitter-Base Voltage (IC=0) V IC Collector Current 15 A ICM Collector Peak Current 20 A IB Base Current 5 [ ... ]

BD743 PDF Datasheet Download