Enable circuit with winding signal detection

A control system for use in a power converter, the control system comprising:

• a primary controller coupled to an input-side of the power converter, the primary controller coupled to receive a request signal comprising a request event, wherein the primary controller is coupled to turn ON a primary switch coupled to the input-side of the power converter to control the transfer of energy between the input-side and an output-side of the power converter;
• and
• a secondary controller coupled to the output-side of the power converter, the secondary controller comprising:
• a request circuit coupled to generate the request signal comprising the request event in response to a feedback signal representative of an output of the power converter;
• a control circuit coupled to generate a secondary drive signal to control a turn ON and a turn OFF of a secondary switch coupled to the output-side of the power converter;
• and
• an enable circuit coupled to receive a winding signal representative of a voltage of an output winding of the power converter and to generate an enable signal in response to a number of times the winding signal falls below a threshold after the request event and a determination that the secondary switch has stopped conduction of a current, wherein the enable circuit outputs the enable signal to enable or disable the control circuit from output of the secondary drive signal to turn ON the secondary switch.