This is the most referenced section in repair scenarios.
Regular repair guides (teardowns) are not schematics. You need proper engineering-level service documentation. nokia 8.1 schematic diagram
A is a technical blueprint showing the electrical connections, components (resistors, capacitors, ICs), and signal pathways of the Nokia 8.1 motherboard. This is the most referenced section in repair scenarios
Qualcomm Snapdragon 710 (SDM710). This handles all primary processing, graphics, and system operations. VPH_PWR is the main system voltage.
Power Management Unit (PMIC) section, Battery Connector page. Look for lines like VBATT , VPH_PWR , CHG_xxx . The VBATT line is the direct connection from the battery. If the phone is powered by a USB cable only, VPH_PWR is the main system voltage.