Load switch circuit and method of controlling battery power using the same

A load switch circuit comprising:

• a charging transistor connected between a first switch node to which a battery voltage is applied and a second switch node and configured to control a charging current in response to a charging control signal;
• a discharging transistor connected between a third switch node to which a charging voltage is applied and the second switch node and configured to control a discharging current in response to a discharging control signal;
• a first current sensor connected to the first switch node and the second switch node and configured to sense the charging current to generate a first current sensing signal;
• a second current sensor connected to the third switch node and the second switch node and configured to sense the discharging current to generate a second current sensing signal;
• a first voltage sensor connected to the first switch node and the second switch node and configured to sense a source-drain voltage of the charging transistor to generate a first voltage sensing signal;
• a second voltage sensor connected to the third switch node and the second switch node and configured to sense a source-drain voltage of the discharging transistor to generate a second voltage sensing signal;
• a first selector configured to select one of the first current sensing signal and the first voltage sensing signal in response to a first mode signal to generate a first selection voltage signal;
• a second selector configured to select one of the second current sensing signal and the second voltage sensing signal in response to a second mode signal to generate a second selection voltage signal;
• a first current controller configured to compare the first selection voltage signal with a first reference voltage to generate the charging control signal;
• and
• a second current controller configured to compare the second selection voltage signal with a second reference voltage to generate the discharging control signal.

A method of controlling battery power, comprising:

• generating a first current sensing signal by sensing a charging current flowing through a charging transistor;
• generating a first voltage sensing signal by sensing a source-drain voltage of the charging transistor;
• generating a first selection voltage signal by selecting one of the first current sensing signal and the first voltage sensing signal in response to a first mode signal;
• and
• controlling the charging current by comparing the first selection voltage signal with a first reference voltage.