This part is a kind of semiconductor called B1240.
Function of this product has 2SB1240.
Manufacturers : ROHM Electronics
Image and pinout :
Some of the text within the PDF file :
2SB1188 / 2SB1182 / 2SB1240 Transistors Medium power transistor (−32V, −2A) 2SB1188 / 2SB1182 / 2SB1240 !Features 1) Low VCE(sat). VCE(sat) = −0.5V (Typ.) (IC/IB = −2A / −0.2A) 2) Complements the 2SD1766 / 2SD1758 / 2SD1862 !External dimensions (Units : mm) 2SB1188 0.5±0.1 2SB1182 1.5±0.3 0.2 4.5 + −0.1 1.6±0.1 0.2 1.5 + −0.1 6.5±0.2 0.2 5.1+ −0.1 C0.5 0.2 2.3 + −0.1 0.5±0.1 9.5±0.5 2.5 +0.2 −0.1 4.0±0.3 0.3 5.5+ −0.1 0.9 1.5 (1) 1.0±0.2 (2) (3) 0.4±0.1 1.5±0.1 0.1 0.4 + −0.05 0.75 0.9 0.65±0.1 !Structure Epitaxial planar type PNP silicon transistor 0.4±0.1 1.5±0.1 0.5±0.1 3.0±0.2 0.55±0.1 2.3±0.2 2.3±0.2 1.0±0.2 ROHM : MPT3 EIAJ : SC-62 (1) Base (2) Collector (3) Emitter (1) (2) (3) ROHM : CPT3 EIAJ : [ ... ]