1.7 Power Supply
1 Hardware Overview
1-14
Libretto 50CT/70CT Maintenance Manual
1.7 Power Supply
The power supply provides two kinds of voltages to the system board, has one
microprocessor operating at 2 MHz, and performs the following functions:
1.
Determines if the Universal AC Adapter or Main Battery Pack is connected to the
computer.
2.
Detects DC output and circuit malfunctions.
3.
Controls the LED icon and the speaker.
4.
Detects a fully charged Main Battery Pack.
5.
Controls power on/off.
6.
Provides more accurate detection of a low Main Battery Pack.
7.
Calculates the remaining Main Battery Pack capacity.
The power supply output rating is specified in Table 1-6.
Table 1-6 Power supply board output rating
DC
Regulation
Use
Name
voltage (V)
tolerance (%)
CPU, RAM, GA,
VGA, VRAM
B3V
+3.3
±5
GA, BIOS ROM,
KBC, PC card
VCC
+12.0
±5
Содержание Libretto 50CT
Страница 8: ...viii Libretto 50CT 70CT Maintenance Manual ...
Страница 10: ...Chapter 1 Hardware Overview ...
Страница 11: ...1 ii Libretto 50CT 70CT Maintenance Manual ...
Страница 30: ...Chapter 2 Troubleshooting Procedures ...
Страница 31: ...2 ii Libretto 50CT 70CT Maintenance Manual ...
Страница 61: ...Chapter 3 Tests and Diagnostics ...
Страница 62: ...3 ii Libretto 50CT 70CT Maintenance Manual ...
Страница 64: ...3 iv Libretto 50CT 70CT Maintenance Manual 3 22 2 Operations 3 45 ...
Страница 128: ...Chapter 4 Replacement Procedures ...
Страница 129: ...4 ii Libretto 50CT 70CT Maintenance Manual ...
Страница 167: ...Appendices ...
Страница 168: ...App ii Libretto 50CT 70CT Maintenance Manual ...
Страница 178: ...Appendix B Board Layout B 4 Libretto 50CT 70CT Maintenance Manual ...
Страница 183: ...Appendix C Pin Assignments Libretto 50CT 70CT Maintenance Manual C 5 ...
Страница 186: ...Appendix Appendix C Pin Assignments C 8 Libretto 50CT 70CT Maintenance Manual 43 GND 44 NC ...
Страница 194: ...Appendix F BIOS Rewrite Procedures F 2 Libretto 50CT 70CT Maintenance Manual ...
Страница 196: ...Appendix G Reliability G 2 Libretto 50CT 70CT Maintenance Manual ...