Datasheet for the 2N7002, a small-signal N-channel enhancement MOSFET usually supplied in SOT-23, as a 94.4 KB PDF. Expect drain-source voltage, continuous drain current, gate threshold, on-resistance and the pin assignment for gate, source and drain. On motherboards and power circuits this device often acts as a level shifter or logic switch, so the sheet helps when checking for a shorted FET, measuring gate drive and finding the correct SMD marking code. Confirm the marking on the part, since many manufacturers make equivalents.
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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The standard format for schematics, block diagrams, power-sequence charts and service manuals.