Pseudo esr technique in a multi-loop low-dropout regulator

A voltage regulator, comprising:

• a first feedback loop, wherein the first feedback loop includes:
• a pass transistor coupled to an input voltage terminal;
• a sense transistor coupled to the pass transistor;
• a control transistor coupled to the sense transistor;
• a cascode transistor coupled to the control transistor;
• and
• a buffer transistor coupled to the cascode transistor and a gate of the sense transistor;
• a resistor having a first terminal and a second terminal, the first terminal coupled to the sense transistor and the control transistor;
• and
• a second feedback loop, wherein the second feedback loop includes:
• an amplifier having a first amplifier input coupled to the second terminal of the resistor, a second amplifier input coupled to a voltage source, and an amplifier output coupled to a gate of the control transistor.

A low-dropout voltage regulator, comprising:

• a pass transistor having a flipped-voltage-follower configuration with a control transistor, wherein a drain of the pass transistor is configured to provide an output voltage of the low-dropout voltage regulator;
• a first feedback loop for the voltage regulator, wherein the first feedback loop is configured to provide a load transient response, and wherein the first feedback loop includes:
• the pass transistor and the control transistor;
• a cascode transistor coupled to the control transistor;
• and
• a buffer transistor coupled to the cascode transistor and a gate of the pass transistor;
• a resistor having a first terminal and a second terminal, the first terminal coupled to the pass transistor and the control transistor;
• and
• a second feedback loop for the voltage regulator, wherein the second feedback loop is configured to provide load regulation, and the second feedback loop includes:
• an amplifier having a first amplifier input coupled to the second terminal of the resistor, a second amplifier input coupled to a voltage source, and an amplifier output coupled to a gate of the control transistor.