Patent ID: 7622905

Claim:
A voltage regulator of a DC power supply comprising: a current-limiting circuit coupled to an output terminal of the DC power supply for limiting a current output from the DC power supply; a power-storing circuit coupled between the current-limiting circuit and a ground terminal of the DC power supply for storing a power output from the DC power supply; and a power-saving circuit, coupled between the output terminal of the DC power supply and the power-storing circuit for saving a power consumed by the current-limiting circuit, comprising: a switch comprising: a first terminal coupled to the output terminal of the DC power supply; a second terminal coupled to the power-storing circuit; and a control terminal; wherein the switch is turned on when a first voltage is higher than a second voltage by a predetermined value; a second resistor connected directly between the second terminal of the switch and the control terminal of the switch; and a third resistor coupled between the control terminal of the switch and the ground terminal of the DC power supply; wherein the second voltage is obtained by dividing the first voltage via the second resistor and the third resistor.