This part is a kind of semiconductor called 2SD2052.

Function of this product has SILICON POWER TRANSISTOR.

Manufacturers : SavantIC

Image and pinout :

Some of the text within the PDF file :

SavantIC Semiconductor Product Specification Silicon NPN Power Transistors 2SD2052 DESCRIPTION ·With TO-3PFa package ·Wide area of safe operation ·Complement to type 2SB1361 APPLICATIONS ·Optimum for the output stage of a HiFi audio amplifier PINNING PIN 1 2 3 Base Collector;connected to mounting base Emitter DESCRIPTION Absolute maximum ratings(Tc=25 ) SYMBOL VCBO VCEO VEBO IC ICP PARAMETER Collector-base voltage Collector-emitter voltage Emitter-base voltage Collector current (DC) Collector current (Pulse) Ta=25 PC Collector power dissipation TC=25 Tj Tstg Junction temperature Storage temperature 100 150 -55~150 CONDITIONS Open emitter Open base Open collector VALUE 150 150 5 9 15 3 W UNIT V V V A A SavantIC Semiconductor Product Specification Silicon NPN [ ... ]

2SD2052 PDF Datasheet Download