I already wrote about the BQ24727 Battery Charger IC that is used in Dell Laptop. Today while inspecting ICs on the motherboard I came across another unfamilar IC which is the VT1318MFQX-1-GP which after bit of research is a power management IC (PMIC), battery charging controller, or a voltage regulator responsible for managing power input from the AC adapter and battery.
Functions of VT1318MFQX-1-GP:
Battery Charging Control – Regulates charging voltage/current from the AC adapter to the battery.
Power Switching – Switches between battery and adapter power.
Voltage Regulation – Used as voltage regulator to provide stable power to other components near the battery connector.
Protection Circuitry – Prevents over-voltage, over-current, or short-circuit conditions.
Symptoms of a Faulty VT1318MFQX-1-GP:
Laptop doesn’t charge the battery.
Laptop doesn’t turn on even with the charger plugged in.
Battery not detected or shows incorrect charge levels.
Random shutdowns or power fluctuations.
Burning smell or overheating near the battery port.
Circuit Diagram
In the dell laptop service manual, I found the circuit diagram where the VT1318MFQX IC chip is used. Below is the circuit implementation.
