Charging apparatus
AssigneeOki Semiconductor Co., Ltd.
InventorKikuo UTSUNO
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Abstract
A charging device can prevent overcharging by coping with a plurality of cell voltages without increasing a circuit area and current consumption. The charging device selects one of at least two judgment voltages in response to a select signal determined depending on a chargeable voltage of a secondary battery. The charging device compares a comparison voltage based on a voltage of a lower stream of a back flow prevention unit with the selected judgment voltage to detect a fully charged state of the secondary battery. The charging device interrupts supply of charging current to the back flow prevention unit upon detecting the fully charged state.
Claims19
A charging apparatus for supplying a charging current to a secondary battery through a back flow prevention unit, the charging apparatus comprising:
- a detector for selecting one of at least two judgment voltages in response to a select signal determined depending on a chargeable voltage of the secondary battery and comparing a comparison voltage based on a voltage of a lower stream of the back flow prevention unit with the selected judgment voltage to detect a fully charged state of the secondary battery;
- the back flow prevention unit;
- and
- an interrupter for interrupting supply of the charging current to the back flow prevention unit when the detector detects the fully charged state.
Dependencies are inferred from the claim text.