A power switching circuit, comprising: a transformer configured to output a first power signal, the transformer including a central-tapped terminal; a rectifying unit coupled to the transformer, the rectifying unit being configured to receive the first power signal and output a second power signal; a first switching unit coupled to the central-tapped terminal of the transformer; and a second switching unit coupled to the rectifying unit and the first switching unit; wherein the power switching circuit is characterized by further comprising: a capacitor; a current sensing component (CS1/CS2) coupled to the first switching unit and the second switching unit, and a feedback unit configured to measure a current passed through the current sensing component (CS1/CS2) and to receive the second power signal, wherein the feedback unit is further configured to measure a voltage of the second power signal so as to detect a voltage level of the second power signal and to output a control signal according to the second power signal for determining whether the first switching unit and the second switching unit are selectively turned on or turned off; wherein in a condition that a voltage level of the second power signal received by the feedback unit is larger than a reference voltage, the feedback unit is configured to turn off the first switching unit and turn on the second switching unit, in a condition that the voltage level of the second power signal received by the feedback unit is smaller than the reference voltage, the feedback unit is configured to turn on the first switching unit and turn off the second switching unit. a transformer configured to output a first power signal, the transformer including a central-tapped terminal; a rectifying unit coupled to the transformer, the rectifying unit being configured to receive the first power signal and output a second power signal; a first switching unit coupled to the central-tapped terminal of the transformer; and a second switching unit coupled to the rectifying unit and the first switching unit; wherein the power switching circuit is characterized by further comprising: a capacitor; a current sensing component (CS1/CS2) coupled to the first switching unit and the second switching unit, and a feedback unit configured to measure a current passed through the current sensing component (CS1/CS2) and to receive the second power signal, wherein the feedback unit is further configured to measure a voltage of the second power signal so as to detect a voltage level of the second power signal and to output a control signal according to the second power signal for determining whether the first switching unit and the second switching unit are selectively turned on or turned off; wherein in a condition that a voltage level of the second power signal received by the feedback unit is larger than a reference voltage, the feedback unit is configured to turn off the first switching unit and turn on the second switching unit, in a condition that the voltage level of the second power signal received by the feedback unit is smaller than the reference voltage, the feedback unit is configured to turn on the first switching unit and turn off the second switching unit. a capacitor; a current sensing component (CS1/CS2) coupled to the first switching unit and the second switching unit, and a feedback unit configured to measure a current passed through the current sensing component (CS1/CS2) and to receive the second power signal, wherein the feedback unit is further configured to measure a voltage of the second power signal so as to detect a voltage level of the second power signal and to output a control signal according to the second power signal for determining whether the first switching unit and the second switching unit are selectively turned on or turned off; wherein in a condition that a voltage level of the second power signal received by the feedback unit is larger than a reference voltage, the feedback unit is configured to turn off the first switching unit and turn on the second switching unit, in a condition that the voltage level of the second power signal received by the feedback unit is smaller than the reference voltage, the feedback unit is configured to turn on the first switching unit and turn off the second switching unit.