Cell protective circuit

摘要

A battery protective circuit which can ensure the safety and reliability of a rechargeable secondary battery is provided. Personal digital assistants include a main circuit (30) and a battery block (60). The battery block (60) includes a battery (20) and a current-amount control circuit (50). The battery (20) is charged via an AC adapter. The current-amount control circuit (50) includes a current and temperature detecting circuit (for example a PTC element) operative to reduce a current amount when an amount of current flowing in the battery (20) approaches a boundary value of a charge-guaranteed region in which the battery (20) is rechargeable.