Over-voltage and under-voltage protection circuit and control method thereof

The invention relates to the technical field of circuits, in particular to an overvoltage and undervoltage protection circuit and a control method thereof.The circuit comprises a power input end, a power supply switch, an undervoltage detection circuit, an overvoltage detection circuit and a load; the power input end, the power supply switch and the load are connected in sequence, and the undervoltage detection circuit and the overvoltage detection circuit are respectively arranged between the power input end and the power supply switch; the under-voltage detection circuit obtains a sampling voltage and an under-voltage threshold value based on an input voltage of the power supply input end, and outputs an under-voltage signal to the power supply switch when determining that the sampling voltage is lower than the under-voltage threshold value; the overvoltage detection circuit is used for outputting an overvoltage signal to the power supply switch when it is determined that the input voltage of the power supp