DC-to-DC converter input stage with capacitive current limit

A method for transferring energy from an input stage to an output stage in a power converter, the method comprising:

• supplying, by a voltage source, an input voltage to the input stage;
• energizing a pair of transformer coils in the input stage, comprising applying, through switching circuitry, an input signal to the pair of transformer coils according to the input voltage;
• stopping drawing current from the voltage source, responsive to an amount of charge drawn from the voltage source reaching a specific value;
• and
• continuing to provide power to the output stage from energy stored in a leakage inductance of the pair of transformer coils for at least a period of time subsequent to said stopping drawing current from the voltage source.

A power converter comprising:

• an input stage comprising:
• a pair of transformer coils;
• switching circuitry configured to energize the pair of transformer coils according to an input supply voltage provided by an input source;
• and
• a limiting circuit coupled between the pair of transformer coils, and configured to cause the input stage to stop drawing current from the input source once an amount of charge drawn from the input source reaches a specific value;
• and
• an output stage configured to receive energy from the pair of transformer coils, and convert the received energy into an output supply voltage;
• wherein the pair of transformer coils are configured to continue providing energy stored in a leakage inductance of the pair of transformer coils to the output stage for at least a period of time, once the limiting circuit has caused the input stage to stop drawing current from the input supply.