ZVS assist snubber for switching converter

1. A voltage converter comprising:

a voltage input;

a transformer comprising a primary winding coupled with the voltage input;

a main switch coupled at a node with the primary winding;

a snubber circuit coupled with the voltage input and with the node, the snubber circuit comprising a controllable switch having a gate and a source; and

a control circuit coupled with the main switch and configured to turn the main switch on and off to convert an input voltage supplied to the voltage input to an output voltage distinct from the input voltage;

wherein the gate is coupled with the source to prevent the controllable switch from turning on; and

wherein the voltage converter is a flyback voltage converter.

2. The voltage converter of claim 1 , wherein the controllable switch comprises a super junction metal-oxide-semiconductor field-effect transistor (MOSFET).

3. The voltage converter of claim 2 , wherein the main switch comprises a non-super junction MOSFET.

4. The voltage converter of claim 2 , wherein the snubber circuit further comprises a capacitor coupled between the controllable switch and the voltage input.

5. The voltage converter of claim 4 , wherein the snubber circuit is absent a bleed resistor coupled in parallel with the capacitor for removing a charge from the capacitor.

6. The voltage converter of claim 2 , wherein the control circuit is configured to turn the main switch on near a minimum value of a valley of a ringing cycle to achieve zero-voltage switching (ZVS).

7. The voltage converter of claim 6 , wherein the valley is a first ringing valley.

8. The voltage converter of claim 6 , wherein the minimum value is zero volts.

9. The voltage converter of claim 8 , wherein the transformer further comprises a secondary winding; and

wherein the voltage converter comprises:

a voltage output; and

a diode coupled between the secondary winding and a first terminal of the voltage output.

10. A method of manufacturing a voltage converter comprising:

coupling a transformer comprising a primary winding coupled with a voltage input;

coupling a main switch with the primary winding at a node;

coupling a snubber circuit with the voltage input and with the node, the snubber circuit comprising a controllable switch having a gate and a source; and

coupling a control circuit coupled with the main switch and configuring the voltage input to turn the main switch on and off to convert an input voltage supplied to the voltage input to an output voltage distinct from the input voltage;

wherein the gate is coupled with the source to prevent the controllable switch from turning on; and

wherein the voltage converter is a flyback voltage converter.

11. The method of claim 10 , wherein the controllable switch comprises a super junction metal-oxide-semiconductor field-effect transistor (MOSFET).

12. The method of claim 11 , wherein the main switch comprises a non-super junction MOSFET.

13. The method of claim 11 , wherein the snubber circuit further comprises a capacitor coupled between the controllable switch and the voltage input.

14. The method of claim 13 , wherein the snubber circuit is absent a bleed resistor coupled in parallel with the capacitor for removing a charge from the capacitor.

15. The method of claim 11 further comprising configuring the control circuit to turn the main switch on near a minimum value of a valley of a ringing cycle to achieve zero-voltage switching (ZVS).

16. The method of claim 15 , wherein the valley is a first ringing valley.

17. The method of claim 15 , wherein the minimum value is zero volts.

18. The method of claim 17 , wherein the transformer further comprises a secondary winding; and

wherein the method further comprises coupling a diode coupled between the secondary winding and a first terminal of a voltage output.