Synchronous rectifying flyback converter with variable input and output voltages

A synchronous rectifying converter configured for receiving a variable input and generating a variable output, comprising:

• a main secondary winding having a first main terminal coupled to a first output terminal and a second main terminal coupled through a switching device to a second output terminal;
• a current storage device and a rectifier coupled in series between the first main terminal and the second main terminal of said main secondary winding;
• and
• a control circuit responsive to a voltage at a connection point between said current storage device and said rectifier to provide a control signal to said switching device.

A method for increasing input and output voltage operating ranges of a synchronous rectifying voltage converter, comprising:

• generating a main voltage at a main secondary winding having a first main terminal coupled to a first output terminal and a second main terminal coupled to a switching device, the switching device being coupled to a second output terminal;
• generating a reference voltage at a first current storage device coupled in series with a rectifier between said first main terminal and said second main terminal;
• generating a control voltage between a switch control terminal of the switching device and a control secondary winding, said control secondary winding having a first control terminal commonly coupled to said rectifier and said first current storage device and a second control terminal coupled to said switch control terminal;
• and
• generating an output voltage, said output voltage regulated by a second current storage device.