The name pairs the 2SK2078 with STW9NA80, an STMicroelectronics-style part number, so this 133 KB PDF may cover both devices or present one as an equivalent. It is filed as a schematic but is presumably datasheet material. The 2SK2078 is a JIS-registered N-channel FET. Use the document to compare voltage and current ratings, on-resistance and package pinout. Verify that both parts really match in the application before substituting one for the other.
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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