This part is a kind of semiconductor called 2SC2581.

Function of this product has AUDIO POWER AMPLIFIER/ DC TO DC CONVERTER(NPN).

Manufacturers : Wing Shing Computer Components

Image and pinout :

Some of the text within the PDF file :

2SC2581 AUDIO POWER AMPLIFIER DC TO DC CONVERTER NPN PLANAR SILICON TRANSISTOR SC-65 ! ! ! High Current Capability High Power Dissipation Complementary to 2SA1106 ABSOLUTE MAXIMUM RATING (Ta=25°C) Characteristic Collector-Base Voltage Collector-Emitter Voltage Emitter-Base voltage Collector Current (DC) Collector Dissipation Junction Temperature Storage Temperature Symbol VCBO VCEO VEBO IC PC Tj Tstg Rating 200 140 6 10 100 150 -55~150 Unit V V V A W °C °C ELECTRICAL CHARACTERISTICS (Ta=25°C) Characterristic Collector Base Breakdown Voltage Collector Emitter Breakdown Voltage Emitter Base Breakdown Voltage Collector Cutoff Current Emitter Cutoff Current *DC Current Gain DC Current Gain Collector- Emitter Saturation Voltage Symbol BVCBO BVCEO BVEBO ICBO IEBO hFE1 hFE2 VCE(sat [ ... ]

2SC2581 PDF Datasheet Download