Overvoltage and overcurrent protection circuit and mobile terminal

A mobile terminal, comprising a cell and a charging and discharging interface, wherein, the mobile terminal further comprises the overvoltage and overcurrent protection circuit, and the overvoltage and overcurrent protection circuit comprises:

• a primary protection circuit, comprising a power end, a detection end, and a low potential interface end, wherein the power end is coupled to an anode of a cell, the detection end is coupled to a cathode of the cell, and the low potential interface end is coupled to a ground end of a charging and discharging interface;
• the primary protection circuit is configured to detect whether there is an over-charging when the cell is charged, and to switch off charging the cell via the charging and discharging interface if there is the over-charging;
• the primary protection circuit is further configured to detect whether there is an over-discharging when the cell is discharging, and switch off discharging of the cell via the charging and discharging interface if there is the over-discharging;
• and
• a secondary protection circuit, comprising a high potential cell end, a low potential cell end, and a high potential interface end, wherein the high potential cell end is externally coupled to the anode of the cell, the low potential cell end is externally coupled to the cathode of the cell, and the high potential interface end is externally coupled to a power end of the charging and discharging interface;
• the secondary protection circuit is configured to perform an overvoltage protection and an overcurrent protection via a fuse when the cell is charged via the charging and discharging interface.

An overvoltage and overcurrent protection method, comprising:

• when a cell is charged, detecting by a primary protection circuit and a secondary protection circuit, a charging voltage and a charging current in real time;
• if a switch-off condition is satisfied, performing at least one act of:
• switching off a charging loop for charging the cell by the primary protection circuit through controlling a MOS transistor and switching off the charging loop by the secondary protection circuit through switching off a fuse, wherein the switch-off condition comprises at least one of:
• the charging voltage being greater than a preset voltage threshold, the charging current being greater than a first preset current threshold, and the cell being fully charged.