BATTERY POLARITY DETERMINATION CIRCUIT, CHARGER, AND ELECTRONIC DEVICE

A battery polarity determination circuit includes a battery accommodating unit including a first contact and a second contact to be in contact with respective electrode terminals of a battery, a control device that is connected via a resistor to a voltage lead-out point at which a voltage of the battery is led out and determines a polarity of the battery, a connection switching circuit capable of switching between a first connection state and a second connection state, and a diode having a cathode to be connected to a voltage read-in point at which the resistor and the control device are connected to each other, and an anode to be grounded, wherein the control device determines the polarity of the battery based on a voltage at the voltage read-in point according to the connection state of the connection switching circuit, and a forward voltage of the diode is set so that the voltage at the voltage read-in point is not less than a lower limit value of an absolute maximum rating of the control device.