Multi-function power control circuit using enhancement mode gallium nitride (GaN) high electron mobility transistors (HEMTs)

A multi-function circuit comprising:

• a low side circuit including a GaN-based low side subordinate half bridge circuit;
• and
• a high side discrete circuit including a GaN-based high side subordinate half bridge circuit;
• wherein each enhancement mode transistor of both the low side circuit and the high side discrete circuit is configured to be an active switching element;
• wherein the GaN-based high side subordinate half bridge circuit is configured to directly drive a GaN high side power switch, the GaN-based high side subordinate half bridge circuit comprises:
• a high side subordinate half bridge high side switch and a high side subordinate half bridge low side switch;
• a state controller comprising a first transistor and a second transistor in electrical communication with the high side subordinate half bridge high side switch and the high side subordinate half bridge low side switch, wherein the state controller is configured to at least determine ON/OFF logic state information of the high side subordinate half bridge circuit;
• and
• a first bootstrap circuit in electrical communication with at least the high side subordinate half bridge high side switch, wherein the first bootstrap circuit is configured to act as a charge pump to control, in combination with the first transistor of the state controller, an on/off state of the high side subordinate half bridge high side switch.

A multi-function circuit comprising:

• a GaN-based low side circuit including:
• a GaN-based low side switch having a low side switch control gate, the low side switch control gate forming a low side subordinate half bridge circuit, and
• a GaN-based low side switch driver having an output connected to the low side switch control gate;
• and
• a GaN-based high side discrete circuit including:
• a GaN-based high side switch having a high side switch control gate, the high side switch control gate forming a high side subordinate half bridge circuit, and
• a GaN-based high side switch driver having an output connected to the high side switch control gate, wherein the GaN-based high side switch driver comprises:
• a high side subordinate half bridge high side switch and a high side subordinate half bridge low side switch;
• a state controller comprising a first transistor and a second transistor in electrical communication with the high side subordinate half bridge high side switch and the high side subordinate half bridge low side switch, wherein the state controller is configured to at least determine ON/OFF logic state information of the high side subordinate half bridge circuit;
• and
• a first bootstrap circuit in electrical communication with at least the high side subordinate half bridge high side switch, wherein the first bootstrap circuit is configured to act as a charge pump to control, in combination with the first transistor of the state controller, an on/off state of the high side subordinate half bridge high side switch;
• wherein each enhancement mode transistor of both the GaN-based low side circuit and the GaN-based high side discrete circuit is a GaN high electron mobility transistor (HEMT) configured to be an active switching element.