Protection circuit and electronic device

A protection circuit that is used with a power supply that produces charging power, and a storage battery for which normal operation is conditional upon a terminal voltage being greater than or equal to a minimum voltage and less than or equal to a maximum voltage, comprising:

• a first switch disposed to a first path that electrically connects the storage battery and the power supply;
• a second switch disposed to a second path that electrically connects the storage battery and a load;
• a voltage detection circuit that detects a terminal voltage of the storage battery;
• an over-charge detection circuit that monitors the storage battery terminal voltage and controls the first switch to turn off when the terminal voltage is detected to exceed the maximum voltage;
• an over-discharge detection circuit that monitors the storage battery terminal voltage and controls the second switch to turn off when the terminal voltage is detected to be below the minimum voltage;
• and
• a control circuit that controls the monitoring operation interval of the over-charge detection circuit and the over-discharge detection circuit according to the terminal voltage of the storage battery detected by the voltage detection circuit.