: If a specific rail (like 3.3V) is missing, low voltage may be injected to identify overheating components using thermal imaging or touch. Documentation & Resources
: Manages the conversion to 3.3V and 5V rails, which are necessary for the standby power state. lac781p schematic top
LA-C781P Motherboard Schematic Overview Compal LA-C781P (often labeled as ) is a common motherboard found in series laptops. It features an AMD Stoney Ridge or similar APU architecture and utilizes the embedded controller. Technical Quick Specs : Compal ABL51 Common Laptop Models : HP 15-af011ur, HP 15-af series Embedded Controller (EC) : ENE KB9022Q Main PWM Controller : Often utilizes the for power rails (e.g., positive 3 cap V cap A cap L cap W cap P positive 5 cap V cap A cap L cap W cap P Troubleshooting Common Issues If you are dealing with a "No Power" (Dead) state, technicians frequently focus on the VIN circuit and the power sequence for the EC. Check the +3VALW rail : Ensure it is reaching pin 15 of the EC (KB9022Q). VIN Circuit : If a specific rail (like 3
Supports DDR3L (1.35V) SDRAM with a maximum capacity of 8GB across two slots. It features an AMD Stoney Ridge or similar
The "top" of the schematic refers to the primary component side. Key landmarks on the LA-C781P top layout include: