Toshiba satellite a20 series User Manual

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1.10 Batteries 
1  Hardware Overview 
 
1.10.3 Battery Charging Control 
Battery charging is controlled by a power supply microprocessor 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. 
 
 Battery Charge 
When the AC adaptor is attached, battery charge starts.   
The times required for quick charges are listed in table 1-9. 
 
Table 1-9  Time required for quick charges 
Status Charging 
time 
Power off 
About 3.5 hours 
Power on 
3.5 to 12.5 hours or longer 
 
NOTE:  The time required for quick charge when power is on is affected by the amount of 
power the system is consuming. Use of the fluorescent lamp and frequent disk access 
consumes power and lengthens the charge time. 
 
If any of the following occurs, the battery charge stops.  
1.  The battery becomes fully charged.  
2.  The AC adaptor or battery is removed.  
3.  The AC adaptor or battery voltage is abnormal 
4.  The charging current is abnormal. 
 
 Detection of full charge 
A full charge is detected when the battery is charging, and under any of the following 
conditions:  
 
1.  The battery charging current drops under the predetermined limit. 
2.  The charging time exceeds the limit. 
3.  The battery’s temperature exceeds 60°C. 
Satellite A20 Maintenance Manual (960-444)   
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