Patent ID: 11936223
Assignee: FDK CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  G  Y | IPC G  H

Claim 0:
1. A battery polarity determination circuit comprising:
a battery accommodating unit including a first contact and a second contact configured to be in contact with respective electrode terminals of a battery accommodated in the battery accommodating unit;
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 from the battery accommodating unit and determines a polarity of the battery accommodated in the battery accommodating unit;
a connection switching circuit capable of switching between a first connection state in which the first contact is connected to the voltage lead-out point and the second contact is grounded, and a second connection state in which the second contact is connected to the voltage lead-out point and the first contact is grounded; 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
wherein 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.