Patent ID: 7714553

Claim:
A voltage regulator, comprising: an amplifier having a first input coupled to a first reference voltage, a second input coupled to a feedback signal, and an output producing a control signal; an output transistor having a control input, a first electrode coupled to a first input voltage, and a second electrode coupled to output a regulated output voltage to an output terminal of the voltage regulator; a feedback circuit coupled to the output terminal of the voltage regulator to produce the feedback signal; an undervoltage detector coupled to the first reference voltage and the feedback signal, producing a charge control signal indicating occurrence of an output undervoltage of at least a first predetermined magnitude; and a charge transistor coupled between a second input voltage and the output terminal, having a control input responsive to the charge control signal to charge the output undervoltage; and a blocking device coupled between the control input of the output transistor and the control input of the charge transistor.