La-e801p Rev 2.0 Schematic -

The primary voltage distribution rail originating from the DC jack or the battery pack (via the charging circuit).

Typically managed by an ENE or Microchip SMSC EC chip, which handles power sequencing, keyboard inputs, thermal monitoring, and battery metrics. 2. Core Power Rails and Sequencing

Technicians use the schematic to trace the +PWR_SRC (main power rail) and ensure the 3.3V and 5V "Always On" rails are present.