Datasheet for the LM317 adjustable positive voltage regulator in a 334 KB PDF. The regulator sets its output from about 1.25 V upward with two resistors and supplies up to roughly 1.5 A in common packages. Technicians use it for the pinout of adjust, output and input, the output voltage formula, dropout figures and protection features. When a supply delivers the wrong voltage, measure the reference across the programming resistor and check both feedback resistors and the input and output capacitors before swapping the chip.
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 @datasheet. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.