PDF datasheet, 113 KB, for the 2SK1690, which the Japanese 2SK numbering identifies as an N-channel FET. It is filed as a schematic but describes a single discrete part, and the name gives no manufacturer or package. The tables inside are what matter when replacing a failed transistor: voltage and current ratings, on-resistance, gate charge and pin order. Check that the replacement footprint matches and that the original marking reads 2SK1690 before ordering parts.
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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