This part is a kind of semiconductor called BD242A.

Function of this product has Medium Power Linear and Switching Applications.

Manufacturers : Fairchild Semiconductor

Image and pinout :

Some of the text within the PDF file :

BD242/A/B/C BD242/A/B/C Medium Power Linear and Switching Applications • Complement to BD241/A/B/C respectively 1 TO-220 2.Collector 3.Emitter 1.Base PNP Epitaxial Silicon Transistor Absolute Maximum Ratings TC=25°C unless otherwise noted Symbol VCEO Parameter Collector-Emitter Voltage : BD242 : BD242A : BD242B : BD242C Collector-Emitter Voltage : BD242 : BD242A : BD242B : BD242C Emitter-Base Voltage Collector Current (DC) *Collector Current (Pulse) Base Current Collector Dissipation (TC=25°C) Junction Temperature Storage Temperature Value - 45 - 60 - 80 - 100 - 55 - 70 - 90 - 115 -5 -3 -5 -1 40 150 - 65 ~ 150 Units V V V V V V V V V A A A W °C °C VCER VEBO IC ICP IB PC TJ TSTG Electrical Characteristics TC=25°C unless otherwise noted Symbol VCEO(sus) Parameter * Collector-E [ ... ]

BD242A PDF Datasheet Download