Indexed as a schematic, this 228 KB PDF carries the short name 16ctq, which resembles a series designation for International Rectifier or Vishay Schottky rectifiers rather than a single complete part number. It probably covers several voltage grades of the same family in one datasheet. Use it to read pinout, forward voltage, reverse leakage and package details when testing or substituting a rectifier on a power board. Match the full suffix on the component to the correct row of the ratings table.
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.