摘要 |
In a charging circuit charging a battery based on a power supply voltage from an external power supply, a charging transistor is provided on a path from the external power supply to the battery. A charging control circuit is integrated on a semiconductor substrate, and adjusts an ON state of the charging transistor to control a charging current supplied to the battery. The voltage adjusting circuit provided on an electric power supply path from the external power supply to a power supply terminal of the charging control circuit generates a necessary voltage drop. The current adjusting circuit adjusts the ON state of the charging transistor such that a voltage of the battery is brought close to a predetermined voltage value. The clamp circuit clamps a voltage at the power supply terminal of the charging control circuit below a predetermined clamp voltage.
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