Switched Mode Power Supplies With Configurable Communication Addresses

A method of supplying power in a switched-mode power supply, the switched-mode power supply comprising an input, an output, a transformer coupled between the input and the output, a synchronous rectifier comprising a drain terminal, a synchronous rectifier controller comprising a supply voltage terminal and a gate terminal, and a circuit coupled between the supply voltage terminal of the controller and the gate terminal of the controller, the method comprising:

• supplying, via the gate terminal of the controller, a control signal to a gate of the synchronous rectifier to selectively conduct current through the secondary winding of the transformer;
• supplying, via the circuit, power from the gate terminal of the controller or the drain terminal of the synchronous rectifier to the supply voltage terminal of the controller;
• and
• wherein the circuit comprises a first capacitor, a first diode, and a buffer comprising two switches, the buffer coupled between a first terminal of the first capacitor and the gate terminal of the controller;
• and
• wherein the method further comprises charging the first capacitor to the DC output voltage minus a forward voltage of the first diode and minus a saturation voltage of one of buffer switches in response to the control signal at the gate terminal of the controller having a logical low value.

A method of supplying power in a switched-mode power supply, the switched-mode power supply comprising an input, an output, a transformer coupled between the input and the output, a synchronous rectifier comprising a drain terminal, a synchronous rectifier controller comprising a supply voltage terminal and a gate terminal, and a circuit coupled between the supply voltage terminal of the controller and the drain of the synchronous rectifier, the method comprising:

• supplying, via the gate terminal of the controller, a control signal to a gate of the synchronous rectifier to selectively conduct current through the secondary winding of the transformer;
• and
• supplying, via the circuit, power from the gate terminal of the controller or the drain terminal of the synchronous rectifier to the supply voltage terminal of the controller;
• wherein the circuit comprises a first capacitor, a first diode, and a buffer comprising two switches, the buffer coupled between a first terminal of the first capacitor and the drain of the synchronous rectifier;
• and
• wherein the method further comprises charging the first capacitor to the DC output voltage minus a forward voltage of the first diode and minus a saturation voltage of one of buffer switches in response to the control signal at the gate terminal of the controller having a logical low value.