Power supply circuit and reuse of gate charge

An apparatus comprising:

• a first switch device;
• a first driver circuit to drive the first switch device;
• a second switch device;
• a second driver circuit to drive the second switch device;
• the first switch device and the second switch device electrically coupled to each other and a node of an inductor through which current is delivered to a load, the first switch device and the second switch device activated at different times based on reuse of switch activation energy;
• and
• a bridge circuit to transfer the switch activation energy between the first driver circuit and the second driver circuit, the first driver circuit and the second driver circuit utilizing the transferred switch activation energy to drive respective gates of the first switch device and the second switch device at the different times;
• and
• wherein the bridge circuit includes an inductor in series with a capacitor, a combination of which couples the first driver circuit to the second driver circuit to transfer of the switch activation energy between the first switch device and the second switch device.

An apparatus comprising:

• a first switch device;
• a first driver circuit to drive the first switch device;
• a second switch device;
• a second driver circuit to drive the second switch device;
• the first switch device and the second switch device electrically coupled to each other and a node of an inductor through which current is delivered to a load, the first switch device and the second switch device activated at different times based on reuse of switch activation energy;
• a bridge circuit to transfer the switch activation energy between the first driver circuit and the second driver circuit, the first driver circuit and the second driver circuit utilizing the transferred switch activation energy to drive respective gates of the first switch device and the second switch device at the different times;
• and
• wherein the bridge circuit includes a resonant circuit coupling the first driver circuit and the second driver circuit, the resonant circuit supporting transfer of a charge between the first switch device and the second switch device to switch between activating the first switch device and the second switch device via reuse of the charge.

A method comprising:

• activating a first switch device by initiating application of charge to a respective gate of the first switch device, activation of the first switch device turning the first switch device to an ON state during which the first switch device conveys current from a first voltage source through an inductor to a load;
• initiating a transfer of the charge from the respective gate of the first switch device to a respective gate of the second switch device, application of the charge to the respective gate of the second switch device causing the second switch device to switch to an ON state during which the second switch device conveys current from a second voltage source through the inductor to the load;
• reusing the charge via the transfer of the charge between the first switch device and the second switch device;
• initiating a transfer of the charge between the first switch device and the second switch device depending on a magnitude of an output voltage applied to the load, the output voltage produced from the current through the inductor;
• utilizing the charge to activate the first switch device while the second switch device is deactivated;
• and
• initiating a transfer of the charge previously used to activate the first switch device from a first driver circuit through a bridge circuit to a second driver circuit that applies the charge to the second switch device to activate the second switch device while the first switch device is deactivated.

An apparatus comprising:

• a first switch device;
• a first driver circuit to drive the first switch device;
• a second switch device;
• a second driver circuit to drive the second switch device;
• the first switch device and the second switch device electrically coupled to each other and a node of an inductor through which current is delivered to a load, the first switch device and the second switch device activated at a different times based on reuse of switch activation energy;
• and
• a bridge circuit to transfer the switch activation energy between the first driver circuit and the second driver circuit, the first driver circuit and the second driver circuit utilizing the transferred switch activation energy to drive respective gates of the first switch device and the second switch device at the different times;
• wherein the first switch device is a first field effect transistor and the second switch device is a second field effect transistor, and
• wherein the first driver circuit applies the switch activation energy to a respective gates of the first field effect transistor to activate the first field effect transistor while the second field effect transistor is deactivated, and
• wherein the second driver circuit applies the witch activation energy to a respective gate of the second field effect transistor to activate the second field effect transistor while the first field effect transistor is deactivated;
• wherein the first driver circuit transfers switch activation energy previously applied to the respective gate of the second field effect transistor to the respective gate of the first field effect transistor;
• and
• wherein the second driver circuit transfers switch activation energy previously applied to the respective gate of the first field effect transistor to the respective gate of the second field effect transistor.