Integrated on-time extension for non-dissipative bleeding in a power supply

A controller for a switched mode power supply, the controller comprising:

• a zero-crossing detector coupled to generate a zero-crossing signal that indicates a zero-crossing condition in the power supply;
• drive logic coupled to the zero-crossing detector to generate a drive logic output signal in response to the zero-crossing signal and in response to a feedback signal representative of an output of the power supply, wherein the drive logic output signal is representative of an on-time of a switch to regulate the output of the power supply;
• and
• a logic gate coupled to receive a first signal representative of a current through the switch and a second signal representative of a zero-crossing time threshold, wherein the logic gate is further coupled to extend the on-time of the switch if the current through the switch is less than a zero-crossing current threshold and the on-time of the switch is less than the zero-crossing time threshold.