Switch mode power supplies including primary side clamping circuits controlled based on secondary side signals

A switch mode power supply comprising:

• an input to receive an input voltage;
• an output to provide an output voltage;
• a power converter coupled between the input and the output, the power converter including a transformer having a primary side and a secondary side, and a clamping circuit, the primary side of the transformer coupled to the input, the secondary side of the transformer coupled to the output, the clamping circuit having at least one switching device coupled to the primary side of the transformer;
• and
• a control circuit coupled to the at least one switching device, the control circuit including at least one isolation component, the control circuit configured to receive a signal from the secondary side of the transformer via the at least one isolation component, and control the at least one switching device coupled to the primary side of the transformer in response to the signal received from the secondary side of the transformer via the at least one isolation component.