Power Supply - Toshiba 650CT Maintenance Manual

1.8

Power Supply

The power supply provides seven kinds of voltages to the system board. The power supply
has one microprocessor and operates at 2 MHz. It contains the following functions:
1. Determines if the AC adapter or battery is connected to the computer.
2. Controls the battery icon and DC IN icon.
3. Detects a fully charged battery.
4. Controls power on/off.
5. Detects low or high voltage at power I/O points.
6. Calculates the remaining battery capacity.
7. When an error occurs, controls LED blinking to indicate the error's source.
8. Controls system reset for Resume mode and boot mode.
9. Controls the LCD/FL power supply according to the LCD panel close sensor.
10. Controls the intensity of the backlight FL.
11. When the power is off, protects the buffer circuits on the system board's gate
arrays.
12. Controls transmission of the main battery status signals.
13. Controls audio signals (beeps) generated by the power supply.
The power supply output rating is specified in Table 1-5.
Use
CPU
CPU, System controller GA,
PCI/ISA-GA, DRAM
video controller, PC card GA,
PC card slot•PCI/Modem-GA
PCI/ISA-GA, video controller,
BIOS-ROM, KBC, LSC
Modem, sound, HDD
PS/2 mouse, PS/2 KB port
PC card slot, B12V
Back-up 5V
Power supply internal use
650CT
Table 1-5 Power supply board output rating
DC
Name voltage (V)
CPUV +2.9
B3V +3.3
VCC +5
IFVCC 5V
12V Yes
B5V 5V
MCV 5V
Power supplied Yes/No
Suspend Power off
Yes No
Yes No
No No
No No
Yes No
Yes No
Yes Yes
No battery
No
No
No
No
No
No
Yes
1-15