Lah103p Schematic New ✦

Typically features a mix of Richtek and Silergy ICs for rail generation. Power Rails and Startup Sequence

Before applying any power, use a multimeter in Ohm mode. Measure the resistance to ground on every major inductor (coil).

3. No Display / Caps Lock Blinking (Missing Power Good Signal)

Repair technicians encounter a few recurring faults on this specific laptop motherboard platform: Shorted Ceramic Capacitors on +19V Rail lah103p schematic new

Once all voltages are stable, the platform reset signal ( PLT_RST# ) goes high, allowing the CPU to start executing BIOS code. 4. Common Failure Points on the LA-H103P

Because the old schematic showed an open-collector output, technicians added pull-up resistors to 5V or 3.3V. The shows this is now unnecessary and harmful. The output is a true voltage output. Adding a pull-up will cause current sinking conflicts and non-linear readings.

Integrated Intel Iris Plus / UHD Graphics or Discrete NVIDIA GeForce MX series GPU Typically features a mix of Richtek and Silergy

Fan spins briefly then stops, power light comes on but no display.

Navigating modern Compal schematics requires understanding their naming conventions:

Multi-layer ceramic capacitors (MLCCs) on the main 19V rail are prone to shorting out over time due to heat and stress. A shorted capacitor pulls the entire B+ line to ground, causing the charger's LED indicator to turn off immediately when plugged into the laptop. Failed +3.3VALW / +5VALW Regulator Common Failure Points on the LA-H103P Because the

What is the on your bench power supply when you plug the board in?

: The laptop does not respond to the power button, and no LEDs illuminate.

The multi-phase buck converters controlled by the PWM IC generate the high-current, low-voltage power needed to initialize the CPU. Common Failure Points on the LA-H103P