Voltage regulator circuit

摘要

A voltage regulator circuit comprises an amplifier (10) having a first input coupled to a first reference voltage node; a power pass element (20) having a control terminal coupled to an output of the amplifier, an input coupled to a power supply input of the voltage regulator circuit, and an output coupled to an output of the voltage regulator circuit; a feedback circuit (30, 31) having an input coupled to the output of the power pass element and an output coupled to a second input of the amplifier; and a compensation module (60) comprising a transistor (61), wherein a gate or base terminal of the transistor is coupled to a second reference voltage node, a drain or collector terminal of the transistor is coupled to the output of the amplifier, and a source or emitter terminal of the transistor is coupled to the power supply input of the voltage regulator circuit. The voltage regulator circuit is capable to increase the power supply rejection ratio of low drop-out voltage regulators.

主权项

1. A voltage regulator circuit, comprising:
an amplifier having a first input coupled to a first reference voltage node; a power pass element having a control terminal coupled to an output of the amplifier, an input coupled to a power-supply input of the voltage regulator circuit, and an output coupled to an output of the voltage regulator circuit; a feedback circuit having an input coupled to the output of the power pass element and an output coupled to a second input of the amplifier; and a compensation module comprising a transistor operating in a saturation region, wherein a gate or base terminal of the transistor is coupled to a second reference voltage node, a drain or collector terminal of the transistor is coupled to the output of the amplifier, and a source or emitter terminal of the transistor is coupled to the power-supply input of the voltage regulator circuit, the transistor operative to increase a power gain of a combination of the amplifier and the compensation module.