Charge control that keeps constant input voltage supplied to battery pack

摘要

A circuit for controlling charging includes a transistor provided on a charging path between a position of a charging terminal and a position of a battery, an input voltage detecting circuit configured to detect a potential of a point on the charging path coupled to the charging terminal's side of the transistor, and a drive circuit configured to control an ON resistance of the transistor between a conductive state and a nonconductive state in response to the potential detected by the input voltage detecting circuit.