Voltage Regulator Circuit

A method for regulating a substantially constant magnitude of an output voltage at an output node, the method comprising:

• generating a bias current via a current source;
• mirroring the bias current via at least one current-mirror to set a first threshold voltage and a second threshold voltage, the first threshold voltage having a magnitude that is greater than the second threshold voltage;
• setting a first current from a first power rail to the output node based on the first threshold voltage;
• setting a second current from the output node to a second power rail, the first and second currents having substantially equal magnitudes during a steady-state condition;
• increasing a magnitude of the first current in response to a transient decrease of the output voltage relative to the first threshold voltage;
• and
• increasing a magnitude of second current in response to a transient increase of the output voltage relative to the second threshold voltage.

A regulator circuit that regulates a substantially constant magnitude of an output voltage at an output node, the circuit comprising:

• means for amplifying a reference voltage based on a bias current to generate an amplified voltage, the amplified voltage having a substantially constant magnitude that is approximately equal to the output voltage;
• means for setting a first threshold voltage and a second threshold voltage based on the amplified voltage, the first threshold voltage having a magnitude that is greater than the amplified voltage and the second threshold voltage having a magnitude that is less than the amplified voltage;
• means for sourcing current to the output node from a first power rail in response to a transient decrease of the output voltage relative to the first threshold voltage;
• and
• means for sinking current from the output node to a second power rail in response to a transient increase of the output voltage relative to the second threshold voltage.