This part is a kind of semiconductor called TIP3055.
Function of this product has Complementary Silicon Power Transistors.
Manufacturers : ON Semiconductor
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TIP3055 (NPN), TIP2955 (PNP) Complementary Silicon Power Transistors Designed for general−purpose switching and amplifier applications. Features • DC Current Gain − hFE = 20 − 70 @ IC = 4.0 Adc • Collector−Emitter Saturation Voltage − VCE(sat) = 1.1 Vdc (Max) @ IC = 4.0 Adc • Excellent Safe Operating Area • These are Pb−Free Devices* MAXIMUM RATINGS Rating Collector − Emitter Voltage Collector − Emitter Voltage Collector − Base Voltage Emitter − Base Voltage Collector Current − Continuous Base Current Total Power Dissipation @ TC = 25°C Derate above 25°C Operating and Storage Junction Temperature Range Symbol VCEO VCER VCB VEB IC IB PD TJ, Tstg Value 60 70 100 7.0 15 7.0 90 0.72 – 65 to + 150 Unit Vdc Vdc Vdc Vdc Adc Adc W W/°C °C THERMAL C [ ... ]