This part is a kind of semiconductor called A1837.
Function of this product has 2SA1837.
Manufacturers : Toshiba Semiconductor
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TOSHIBA Transistor Silicon PNP Epitaxial Type 2SA1837 Power Amplifier Applications Driver Stage Amplifier Applications 2SA1837 Unit: mm • High transition frequency: fT = 70 MHz (typ.) • Complementary to 2SC4793 Maximum Ratings (Tc = 25°C) Characteristics Collector-base voltage Collector-emitter voltage Emitter-base voltage Collector current Base current Collector power dissipation Ta = 25°C Tc = 25°C Junction temperature Storage temperature range Symbol VCBO VCEO VEBO IC IB PC Tj Tstg Rating −230 −230 −5 −1 −0.1 2.0 20 150 −55 to 150 Electrical Characteristics (Tc = 25°C) Unit V V V A A W °C °C JEDEC ― JEITA ― TOSHIBA 2-10R1A Weight: 1.7 g (typ.) Characteristics Collector cut-off current Emitter cut-off current Collector-emitter breakdown [ ... ]