La-c781p Schematic Jun 2026
Gate of PQ101 is driven by (BAT100). Schematic shows gate should be pulled low by charger IC’s ACDRV (pin 4). Measure ACDRV – 0V. BQ24780S is faulty.
For professional-level repair, you need two types of documents:
Order replacement (common chip). After replacing, ACDRV rises to 25V, +PWR_SRC = 19.5V. Still no 3.3V_ALW. La-c781p Schematic
The La-C781P schematic is a comprehensive diagram that illustrates the intricate relationships between various components on the motherboard. This diagram is essential for:
: Look for corroded vias near the liquid-damage-prone audio and charging sections. Gate of PQ101 is driven by (BAT100)
The schematic cleverly shows a "Back Drive Protection" circuit. If you inject 19V directly onto the main cap without consulting the schematic, you might blow a fuse you didn't know existed. But worse, the schematic highlights that (a TVS diode) is designed to short to ground if voltage spikes above 22V.
Verify Connections: Ensure there are no broken traces or cold solder joints that could be interrupting the electrical path. BQ24780S is faulty
The LA-C781P is the motherboard model number (often referred to as a "Compal" board, as Compal Electronics manufactures many Dell motherboards). You will typically find this board inside:
The Ultimate Guide to the Compal LA-C781P Motherboard Schematic