This part is a kind of semiconductor called B1566.

Function of this product has Power Transistor.

Manufacturers : Rohm

Image and pinout :

Some of the text within the PDF file :

Transistors 2SB1566 For Power Amplification (−60V, −3A) 2SB1566 zStructure PNP Silicon Epitaxial Planar Transistor zFeatures 1) Low VCE (sat). 2) Wide SOA. zApplications Relay drive DC-DC converter Stabilized power supply zExternal dimensions (Unit : mm) TO-220FN 10.0 φ3.2 4.5 2.8 15.0 12.0 8.0 14.0 5.0 1.2 1.3 (1)Base (2)Collector (3)Emitter 0.8 2.54 2.54 (1) (2) (3) 0.75 zComplements PNP 2SB1566 NPN 2SD2395 2.6 zAbsolute maximum ratings (Ta=25°C) Parameter Collector-base voltage Collector-emitter voltage Emitter-base voltage Collector current DC Pulse Collector power dissipation Junction temperature Storage temperature ∗1 Pw=100ms, single pulse Symbol VCBO VCEO VEBO IC ICP PC Tj Tstg Limits Unit −60 V −50 V −5 V −3 A(DC) −4.5 A(Pulse)�� [ ... ]

B1566 PDF Datasheet Download