This part is a kind of semiconductor called 2SA1020.

Function of this product has One Watt High Current PNP Transistor VOLTAGE AND CURRENT ARE NEGATIVE.

Manufacturers : ON Semiconductor

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2SA1020 Preferred Device One Watt High Current PNP Transistor Features • Pb−Free Packages are Available* MAXIMUM RATINGS Rating Collector −Emitter Voltage Collector −Base Voltage Emitter −Base Voltage Collector Current − Continuous Total Power Dissipation @ TA = 25°C Derate above 25°C Total Power Dissipation @ TC = 25°C Derate above 25°C Operating and Storage Junction Temperature Range Symbol VCE VCB VEB IC PD PD TJ, Tstg Value 50 50 5.0 2.0 900 5.0 1.5 12 −55 to +150 Unit Vdc Vdc Vdc Adc mW mW/°C W mW/°C °C http://onsemi.com VOLTAGE AND CURRENT ARE NEGATIVE FOR PNP TRANSISTORS COLLECTOR 2 3 BASE 1 EMITTER PNP THERMAL CHARACTERISTICS Characteristic Thermal Resistance, Junction−to−Ambient Thermal Resistance, Junction−to−Case Symbol RqJ [ ... ]

2SA1020 PDF Datasheet Download