Toshiba T2150 series Maintenance Manual page 19

1.10.3 Backup Battery
The backup battery maintains data for AutoResume. The power source used to back-up the
AutoResume data is determined according to the following priority:
AC power > Main battery > Backup battery
The backup battery is charged by the main battery or AC power cord when the system is
powered on. Table 1-11 shows the charging time and data preservation period of the backup
battery.
Table 1-11 Backup battery charging/data preservation time
Charging Time
Data preservation period (full charge)
1.10.4 RTC Battery
The RTC battery provides power to keep the current date, time, and other setup information
in memory while the computer is turned off. Table 1-12 shows the charging time and data
preservation period of the RTC battery.
Table 1-11 RTC battery charging/data preservation time
Charging Time
Data preservation period (full charge)
T2150 Series
Power On
Power Off (with AC power)
Power Off (Without AC power) Doesn't charge
With AC power
or main battery
Time
20 H
20 H
5 H
Time
48 H
1 month
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