Power Supply - Toshiba Satellite A40 Maintenance Manual

1.12 Power Supply

1.12 Power Supply
The power supply supplies many different voltages to the system board and performs the following
functions:
1. Checks power input to determine:
Whether the AC adaptor is connected to the computer.
Whether the battery pack is installed and supplying power.
2. Checks power supply's internal controls:
Battery pack charging: start, stop and voltage supplied to the battery pack.
Power supply system: Power supplied from a DC power source (AC adaptor).
Faulty power supply: Executes forced shutdown if needed.
Logic: Power supply to various circuits
Charging current to PWM control IC for battery pack charging
3. Controls the following aspects of the logic system
Power supply to gate arrays
Power on/off
4. Indicates the following:
DC IN (sets LED to orange or blue)
Battery icon (sets LED to orange or blue)
Faulty power supply by low battery
5. Interface for the following:
BIOS via EC/KBC
Function mode of power supply
6. Detects the following:
Input voltage to logic system
Input voltage, overvoltage and input/output to battery pack
Battery pack's internal temperature
Input voltage to DC power supply (output from AC adaptor)
The power supply output rating is specified in Table 1-11.
Satellite A40 Maintenance Manual (960-458)
1 Hardware Overview
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