Power Supply Hardware Overview

1.11 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 green)

∙Battery icon (sets LED to orange or green)

∙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 1-9.

TECRA M1 Maintenance Manual (960-436)

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