Toshiba A40 manual Hardware Overview Power Supply

1 Hardware Overview 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.

1-32 Satellite A40 Maintenance Manual (960-458)