Datasheet for the 2SD2258 NPN bipolar transistor, supplied as a 56.8 KB PDF and filed under schematics. The trailing _E in the name identifies a document edition and says nothing about the part itself. The JIS 2SD code covers NPN low-frequency transistors, often printed on the body without the 2S prefix, so a device marked D2258 refers to the same type. Use the absolute maximum ratings and pin diagram to judge whether a substitute is safe in a power or driver stage.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
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