Low-Dropout Voltage Regulator

摘要

A low-dropout voltage regulator includes a power transistor configured to receive an input voltage and to provide a regulated output voltage at an output voltage node. The power transistor includes a control electrode configured to receive a driver signal. A reference circuit is configured to generate a reference voltage. A feedback network is coupled to the power transistor and is configured to provide a first feedback signal and a second feedback signal. The first feedback signal represents the output voltage and the second feedback signal represents an output voltage gradient. An error amplifier is configured to receive the reference voltage and the first feedback signal representing the output voltage. The error amplifier is configured to generate the driver signal dependent on the reference voltage and the first feedback signal. The error amplifier includes an output stage that is biased with a bias current responsive to the second feedback signal.

主权项

1. A method of operating a low-dropout voltage regulator, the method comprising:
receiving a first feedback signal at a feedback network from a transistor coupled to an output of the low-dropout voltage regulator, the first feedback signal representing an output voltage at the output; generating a second feedback signal at the feedback network, the second feedback signal comprising a time derivative of the output voltage; receiving a reference voltage and the first feedback signal at an error amplifier; generating, at the error amplifier, a drive signal for the transistor dependent on the reference voltage and the first feedback signal; and biasing an output stage of the error amplifier with a bias current proportional to the second feedback signal.