Power Supply - Toshiba satellite A20 series Maintenance Manual

1 Hardware Overview
1.9

Power Supply

The power supply distributes many different voltages to the system board and performs the
following functions:
1. Input port management
•
AC adaptor connection
•
Battery pack installation
•
The voltage of AC adaptor (both IN and OUT)
2. Power supply internal control
•
Battery pack charging status (ON/OFF)
•
Controls DC voltage output by AC Adaptor
•
Regulates power supply to system components (load and logic circuits)
•
Controls circuit breakers in event of a power supply malfunction
3. Management of power to logic circuits
•
Controls power to the CPU
•
Regulates power supplied to gate arrays
•
Controls ON/OFF power
4. Status indicators
•
DC IN LED
•
Battery LED
5. External device interface
•
Monitors I
•
Transmits the power supply mode.
6. Monitors power output
•
Power to systems components (load and logic circuits)
•
Battery pack voltage, overvoltage and I/O current
•
Battery pack internal temperature
1-26
2
C bus connections through EC/KBC on the system board.
1.9 Power Supply
Satellite A20 Maintenance Manual (960-444)