Half bridge circuit with bootstrap capacitor charging circuit

Abstract

A half bridge circuit is disclosed. The half bridge circuit includes a low side transistor having a low side transistor gate, where a low side transistor gate voltage at the low side transistor gate is controlled by a low side gate signal. The half bridge circuit also includes a high side transistor having a high side transistor gate, where a high side transistor gate voltage at the high side transistor gate is controlled by a high side gate signal. The half bridge circuit also includes a semiconductor circuit configured to allow current to flow from a ground referenced power supply node to a first floating power supply terminal. The semiconductor circuit includes a first transistor, where a gate voltage is controlled by a gate drive circuit control signal, a source is connected to the ground referenced power supply node, and a drain connected to the first floating power supply terminal.

What is claimed is: 
     
         1 . A half bridge circuit, comprising:
 a low side GaN-based transistor having a low side transistor gate, wherein a low side transistor gate voltage at the low side transistor gate is controlled by a low side gate signal; and   a high side GaN-based transistor having a high side transistor gate, wherein a high side transistor gate voltage at the high side transistor gate is controlled by a high side gate signal.