Patent ID: 8143872

Claim:
A power regulator for converting an input voltage to an output voltage, said power regulator comprising: a pass device receiving said input voltage and providing said output voltage at an output terminal of said power regulator; a reference signal circuit coupled to said output terminal and powered by said output voltage, said reference circuit providing a reference signal; an error amplifier coupled to said pass device and powered by said output voltage, said error amplifier comparing said reference signal with a feedback signal indicative of said output voltage, and generating a control signal according to a result of said comparison to drive said pass device; and a start-up circuit coupled to said pass device and powered by said input voltage, said start-up circuit generating a start-up signal; wherein said pass device is driven by said start-up signal during a start-up duration of said regulator, and wherein said pass device is driven by said control signal during a normal operation of said regulator, and wherein said start-up circuit comprises a current generator generating a first current as said start-up signal, wherein said error amplifier generates a second current as said control signal, and wherein said first current is conducted to said pass device during said start-up duration, and said second current is conducted to said pass device during said normal operation.