Dual low voltage IC based high and low side gate drive

High and low-side gate drivers are required in most switching power converters to provide on/off control of both ground referenced and floating switches. The drivers are required to provide sufficient current to the gates to meet timing requirements, provide a floating supply to the high-side device, and create a proper dead time between the switches to avoid simultaneous conduction. A method is proposed that uses two low-voltage integrated circuits (LVICs) to provide high and low-side gate drive in high-voltage applications. A coupling capacitor is placed between the two ICs to provide three functions: (1) high-voltage isolation, (2) high and low-side power supply, and (3) signaling to the high-side for on/off control. Integrated switches are used on each IC to provide active current steering for charge-pump power supply operation and current sensing for signaling detection. The required key blocks for IC fabrication are also discussed. A discrete test-bed is built to verify charge-pump operation as well as the characteristic current flowing through the coupling capacitor for detection and sequencing through the operating modes.