Patent ID: 7227343

Claim:
A linear voltage regulator with a selectable output voltage comprising: a regulating means comprising an input pole for receiving an input voltage, an output pole for providing an output voltage to a load, and a controlling pole for receiving a driving voltage; a transistor comprising a base, an emitter being grounded, and a collector being connected to the controlling pole; a first resistor and a second resistor directly connected between the output pole of the regulating means and ground for receiving the output voltage; and a voltage sampling control circuit electrically connected to a node between the first resistor and the second resistor comprising a third resistor and a fourth resistor, a common terminal of the third resistor and the fourth resistor being connected to the node between the first resistor and the second resistor, the other terminals of the third resistor and the fourth resistor acting as controlling signal input ends for receiving logic signals from a controlling chip, the voltage sampling control circuit generating a reference current to the base of the transistor to provide a selectable output voltage.