Charge/discharge control circuit, charge/discharge control device, and battery device

A charge/discharge control circuit formed on a semiconductor substrate, the charge/discharge control circuit comprising:

• a power supply terminal open detection circuit configured to detect whether a power supply terminal connected to the semiconductor substrate is in an open state in which the power supply terminal is not externally connected, and provide an open detection result signal including a signal level corresponding to a detection result;
• an overdischarge detection circuit configured to detect whether a secondary battery is in an overdischarge state, and provide an overdischarge detection result signal including a signal level corresponding to a detection result;
• a control circuit configured to perform open/close control of a charge/discharge path of the secondary battery;
• and
• an overdischarge mask circuit configured to mask the overdischarge detection result signal supplied from the overdischarge detection circuit to the control circuit in a case in which the open detection result signal supplied from the power supply terminal open detection circuit to the control circuit includes a signal level corresponding to the open state.