Schematic package named G721U.W, ZIP of about 1.73 MB, filed under Samsung; the code most likely refers to an SM-G781U-style US model but the name states only G721U with a W suffix, so confirm the exact model code on the phone before using it. The W token is not explained. Service schematics of this kind help trace PMIC rails, charging paths, connector pinouts and signal lines, and support locating shorts. Check that board markings match before relying on part references.
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 @phoneSchematics. Enginerys does not host this file.
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