Toshiba Satellite L300 Series, Maintenance Manual

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1 Hardware Overview 1.6 Power Supply
20 Satellite L300D/L305D/Satellite Pro L300D/EQUIUM L300D/SATEGO L300D Maintenance Manual
1.6 Power Supply
The power supply unit provides many different voltages for the system board and performs the
following functions:
1. Power input monitor
Checks whether the DC power supply (AC adapter) is connected to the computer.
Checks whether the battery pack is connected to the computer.
Monitors the DC power supply input voltage (AC Adapter output voltage).
2. Power supply's internal control
Turns on and off the battery pack charging power supply.
Issues a charging current instruction to the PWM control IC of the battery pack charging
power supply.
Controls the supply of DC power supply input (AC Adapter output) to the power supply
unit.
Controls the supply of power to the system block (load/logic circuit side).
Controls forced shutdown if the power supply malfunctions.
3. Logic circuit control
Instructs the gate array to enable/disable tuning the power on.
Controls power-on/off operation.
4. Status display
Turns on the Power LED (in Green or AMBER).
Battery indicator (in Green or AMBER or AMBER Flash).
5. External interface
Performs communication through the I2C bus (via the internal EC/KBC).
Transfers the power supply operation mode.
6. Output monitor
Monitors the voltage output to the system block (load/logic circuit side).
Monitors the voltage, over voltage, input/output current of the battery pack.
Monitors the internal temperature of the battery pack.
Monitors the supply voltage from the AC adapter.