Lac781p Schematic Top Official

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

You cannot directly parallel two LAC781P chips because the error amplifiers will conflict. Use the schematic top to understand why: each regulator tries to control its own output voltage, leading to one hogging all the current. Instead, use a single higher-current regulator or add ballast resistors. lac781p schematic top

The fan gave a sudden, sharp spin. On the bench, the HP logo flickered to life. The Check the +3VALW rail : Ensure it is

The schematic outlines several vital power Rails and ICs required for the laptop to boot: Instead, use a single higher-current regulator or add

The 3V RTC cell power is active even before the charger is connected.