dynabook Satellite C40-G, Manual

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SATELLITE PRO C40-G, SATELLITE C40-G Maintenance Manual
so that it can resume it.
1.52
Battery Charging Control
Battery charging is controlled by TI BQ24780S. When AC adapter and battery
pack are attached to the computer, BQ24780S controls the charge on/off state
and detects a full charge.

Battery Charge
When the AC adapter is attached, the battery is charged by off-state charge when the system is
powered off or by on-state charge when it is powered on.
Table 1-3 Quick/Normal Charging Time
State Charge Time
Off-State Charge 2 Cell Less than 4 hours
On-State Charge
2 Cell over 4 hours
Any of the following cases stops battery charge:
1. The battery becomes fully charged.
2. The AC adapter or battery pack is removed.
3. The battery or AC adapter voltage is abnormal.

Detection of full charge
A full charge is detected only when the battery is being charged by quick or
normal charge. A full charge is detected when either of the following
conditions is met:
1. The current in the battery charging circuit drops below the
NOTE: The time required for normal charge depends on the power consumption by the
system. Using the fluorescent lamp and frequently accessing the disk consume much power
and lengthen the charge time.