Datasheet in PDF for the ICL8038, here likely an Intersil version given the I in the name, a precision waveform generator and voltage-controlled oscillator producing sine, square and triangle outputs. The 363 KB document includes pinout, frequency formulas, duty-cycle and distortion adjustment circuits and electrical characteristics. Useful when repairing older function generators, it lets you check timing resistors and capacitor, supply rails and sweep input, and find substitutes such as XR8038 equivalents for this long-discontinued 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.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.