Error amplifier with built-in over voltage protection for switched-mode power supply controller

A method, comprising:

• in a first amplification circuit,
• receiving at a first input a reference signal having a voltage;
• receiving at a second input a feedback signal having a voltage representing the amplitude of a load voltage;
• providing at a first output a difference signal representing a difference between the reference signal and the feedback signal;
• generating a control signal as a function of the difference between the reference signal and the feedback signal;
• and
• providing the control signal at a second output;
• and
• in a second amplification circuit,
• receiving the control signal, and
• adjusting an operating current of the second amplification circuit by an amount indicated by the control signal.

A switched mode power supply, comprising:

• a switch that when closed connects a voltage source to an energy storage circuit;
• a switching signal generator providing a switching signal to open and close the switch, the switching signal based in part on a difference signal;
• a sensing circuit providing a feedback signal representing the voltage at an output of the energy storage circuit;
• an error amplifier including
• a first amplification circuit that compares the feedback signal to a reference signal and provides the difference signal based on the comparison;
• and
• a second amplification circuit that generates a control signal based at least in part on the feedback signal and the reference signal;
• and
• a compensation circuit that receives the control signal and adjusts an operating current of the compensation circuit based on the control signal.