Low-power mode for power supply with two-stage driver

A power supply, comprising:

• a flyback converter;
• a flyback controller coupled to an input of the flyback converter, the flyback controller having a reference input and a feedback input;
• a first voltage divider coupled to the reference input;
• a second voltage divider coupled to the feedback input;
• and
• a low-power-mode circuit configured to cause one of a first voltage at the reference input or the second voltage at the feedback input to change in response to a control signal indicating an operational change from a high-power mode to a low-power mode.

A method, comprising:

• providing, within a flyback converter, a DC input voltage to a primary side of a transformer;
• generating an output signal from a flyback controller at least in part in response to a voltage at an input pin of the flyback controller;
• modifying a first flow of current through the primary side of the transformer at least in part in response to the output signal from the flyback controller;
• directing a DC output voltage from a secondary side of the transformer to a first-stage load;
• converting, with a DC-DC converter, the DC output voltage to a lower DC output voltage for a second-stage load;
• receiving activation of a low-power-mode signal;
• at least in part in response to the activation, causing the DC output voltage to decrease to a low-power-mode DC output voltage at least by changing the voltage at the input pin of the flyback controller while continuing to generate the output signal.