Schematic in PDF form, 2.82 MB, labelled only G52 with a website tag appended to the name. The name does not state the brand, so the model cannot be confirmed from it alone; open the PDF and check the title block and board markings against your device. Phone schematics like this are used to follow charging and power circuits, identify the PMIC and trace signals to the display, camera, keypad and SIM connectors. Any standard PDF reader opens it, and text search helps when looking up component 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 @mobileshematic. 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.