Patent ID: 9131036
Filing Date: 2015-09-08
Classification: H02H,H02J,H04M

Abstract:
1. A mobile terminal, comprising a charging port, a power management unit (PMU) and a battery, wherein the mobile terminal further comprises a charging surge protection circuit disposed between the charging port and the PMU; the charging surge protection circuit comprises a low-pass filtering circuit, a switch control circuit, a diode and a first resistor; the low-pass filtering circuit has an input terminal connected to an output terminal of the charging port, and an output terminal connected to a first input terminal of the PMU; the switch control circuit has a first input terminal connected to the low-pass filtering circuit, a second input terminal connected to an output terminal of the PMU, and an output terminal connected to the first resistor via the diode; and the first resistor is connected to an anode of the battery, and a cathode of the battery is grounded, wherein a cathode of the diode is connected to a second input terminal of the PMU and the anode of the battery is connected to a third input terminal of the PMU; wherein during a battery charging process of the mobile terminal, a charging current flows from the charging port and passes through the low-pass filtering circuit, the switch control circuit, the diode, the first resistor and the battery in sequence to charge the battery; wherein the switch control circuit comprises a metal oxide semiconductor (MOS) transistor and a second capacitor; the MOS transistor has a source connected to the first input terminal of the PMU, a gate connected to the output terminal of the PMU, and a drain connected to the diode; and the second capacitor has one end connected to the source of the MOS transistor and the other end connected to the gate of the MOS transistor.