This part is a kind of semiconductor called C4581.

Function of this product has 2SC4581.

Manufacturers : SavantIC

Image and pinout :

Some of the text within the PDF file :

www.datSasaheveat4nu.tcIoCm Semiconductor Silicon NPN Power Transistors Product Specification 2SC4581 DESCRIPTION ·With TO-3PML package ·High voltage,high speed ·Switching power transistor PINNING PIN 1 2 3 DESCRIPTION Base Collector Emitter Fig.1 simplified outline (TO-3PML) and symbol Absolute maximum (Ta=25 ) SYMBOL PARAMETER VCBO VCEO VEBO IC ICM IB IBM PC Tj Tstg Collector-base voltage Collector-emitter voltage Emitter-base voltage Collector current Collector current-peak Base current Base current-peak Collector power dissipation Junction temperature Storage temperature CONDITIONS Open emitter Open base Open collector TC=25 THERMAL CHARACTERISTICS SYMBOL PARAMETER Rth j-c Thermal resistance junction to case VALUE 600 450 7 10 20 4 8 65 150 -55~150 UNIT V V V A A A [ ... ]

C4581 PDF Datasheet Download