Controller for a switched mode power supply and associated methods

A controller for a switched mode power supply, wherein the controller is configured to be connected to a first-conduction-channel terminal, a second-conduction-channel terminal and a control terminal of a synchronous rectifier, the controller comprising:

• a voltage comparator configured to determine satisfaction of a voltage criterion, wherein the voltage criterion is satisfied when a conduction channel voltage between the first-conduction-channel terminal and the second-conduction-channel terminal meets a first pre-determined voltage threshold;
• and
• a timer configured to determine satisfaction of a time criterion, wherein the time criterion is satisfied when a voltage associated with the synchronous rectifier meets a second predetermined voltage threshold for greater than a pre-determined time;
• the controller configured to provide for a normal mode of operation based on satisfaction of the voltage criterion and a power-saving mode of operation based on satisfaction of the time criterion, wherein the controller is configured to draw a power-saving-mode current in the power-saving mode of operation, and draw a normal-mode current in the normal mode of operation, wherein a magnitude of the normal-mode current is greater than a magnitude of the power-saving-mode current.