1 Hardware Overview 1.6 Batteries
1-18 [CONFIDENTIAL] Satellite M40X Maintenance Manual
1.6.1 Main Battery
Battery charging is controlled by a power supply microprocessor that is mounted on the system
board. The power supply microprocessor controls whether the charge is on or off and detects a
full charge when the AC adaptor and battery are attached to the computer. The system charges
the battery using quick charge or trickle charge.
? Quick Battery Charge
When the AC adaptor is attached, there are two types of quick charge: quick charge when
the system is powered off and normal charge when the system is powered on.
The times required for charges are listed in the table below.
Status Charging time
Normal charge (power on) 12 hours or longer
Quick charge (power off) About 4 hours
NOTES
1. The time required for normal charge is affected by the amount of power the system
is consuming. Use of the fluorescent lamp and frequent disk access diverts power
and lengthens the charge time.
2. Using quick charge, the power supply microprocessor automatically stops the
charge after eight hours regardless of the condition of the battery. Overcharging
could cause the battery to explode.
If any of the following occurs, the battery quick charge process stops.
1. The battery becomes fully charged.
2. The AC adaptor or battery is removed.
3. The battery or output voltage is abnormal.
4. The battery temperature is abnormal.
5. The battery SMBus communication fails.
6. The battery cell is bad.
? Detection of full charge
A full charge is detected from the battery pack through SMBus when the battery is
charging.