Controller for resonant power converter, resonant power converter and method of operating a resonant power converter

A method comprising:

• controlling a switch of a resonant power converter during a normal operation mode;
• terminating execution of the normal operation mode in response to detecting an exception condition;
• after terminating the execution of the normal operation mode, controlling the switch for at least one time period to discharge a voltage from a resonant capacitor of the resonant power converter;
• and
• wherein the at least one time period comprises a plurality of time periods separated by further time periods, the method further comprising:
• setting time durations of the plurality of time periods depending on a received signal indicating a voltage stored in the resonant capacitor.

A controller including control logic operative to:

• control a high side switch and a low side switch of a resonant power converter during a normal operation mode;
• terminate execution of the resonant power converter in the normal operation mode in response to determining an exception condition;
• after terminating the execution of the resonant power converter in the normal operation mode, control operation of the high side switch and the low side switch for at least one time period to discharge a resonant capacitor of the resonant power converter;
• wherein the at least one time period includes a first control cycle and a second control cycle;
• and
• wherein the control logic is further operative to, during the control operation of the high side switch and the low side switch for the first control cycle:
• discharge the resonant capacitor via deactivation of the high side switch to an off state for a full duration of the first control cycle and activation of the low side switch to an on state for a less than all portion of the first control cycle;
• and
• wherein the control logic is further operative to, during the operation of the high side switch and the low side switch for the second control cycle:
• discharge the resonant capacitor via deactivation of the high side switch to the off state for a full duration of the second control cycle and activation of the low side switch to the on state for a less than all portion of the second control cycle.

A controller including control logic operative to:

• control a first switch and a second switch of a resonant power converter during a first operational mode, the first switch and the second switch connected in series, the first switch and the second switch alternatingly controlled ON and OFF during the first operational mode to supply current through a series circuit path including a resonant capacitor and a first transformer winding;
• terminate execution of the resonant power converter in the first operational mode in response to detecting an exception condition;
• and
• in response to the exception condition, after terminating the execution of the resonant power converter in the first operational mode, control operation of the first switch and the second switch in accordance with a second operational mode during which the control logic is operative to:
• i) control operation of the first switch to an off-state for a full duration of a first control cycle, and ii) control operation of the second switch to an on-state for at least a portion of the first control cycle to discharge energy stored in the resonant capacitor of the resonant power converter.