Method and circuit for peak power in quasi-resonant converters

A control circuit for a switched-mode power supply, the control circuit comprising:

• a switch controller for operating the switched-mode power supply in an on-state or an off-state;
• a counter circuit for timing a duration of an off-state during a nominal load condition of the switched-mode power supply;
• a register in communication with the counter circuit for storing the off-time duration during the nominal load condition;
• and
• a peak power excursion detection circuit for detecting a peak power excursion condition of the switched-mode power supply;
• wherein a switching frequency of the switch controller is based on the off-time duration stored in the register after the peak power excursion condition of the switched-mode power supply is detected.

A switched-mode power supply circuit for powering a load, the switched-mode power supply circuit comprising:

• a switching circuit for operating the switched-mode power supply in an on-state or an off-state, wherein power is stored in a power storage circuit during the on-state;
• a switch controller for operating the switching circuit such that the switched-mode power supply alternates between the on-state and the off-state at a switching frequency;
• a counter circuit for timing a duration of a particular off-state during a nominal load condition of the switched-mode power supply;
• a register in communication with the counter circuit for storing the off-time duration of the particular off-state during the nominal load condition;
• and
• a peak power excursion detection circuit for detecting a peak power excursion condition of the switched-mode power supply;
• wherein the a off-time of the switch controller is based on the off-time duration stored in the register after the peak power excursion condition of the switched-mode power supply is detected.