Toshiba Satellite A40 Maintenance Manual - Page 52

1 Hardware Overview 1.13 Batteries 1.13.2 Battery Charging Control Battery charging is controlled by a power supply microprocessor. The 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. Quick Battery Charge When the AC adaptor is attached, there are two types of quick charge: quick charge 1 when the system is powered off and quick charge 2 when the system is powered on. Table 1-13 Time required for quick charges Status Quick charge 1 (Power off) Quick charge 2 (Power on) Charging time About 3.5 hours About 7.0 to 20.0 or longer NOTE: The time required for quick charge 2 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. 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. q Detection of full charge A full charge is detected only when the battery is charging at quick charge. A full charge is detected under any of the following conditions: 1. The current in the battery charging circuit drops under the predetermined limit. 2. The charging time exceeds the fixed limit. 1-36 Satellite A40 Maintenance Manual (960-458)