Dc-dc converters with n-channel high-side switches using high-side drivers having low voltage controls and floating level shifters

A circuit comprising:

• a first switch coupled to a second switch at a switch node;
• a driver circuit coupled to the first switch;
• a first bootstrap switch;
• a first bootstrap capacitor coupled to the switch node and to the first bootstrap switch, the first bootstrap capacitor arranged to supply a first power voltage to the driver circuit;
• a pre-driver circuit coupled to the driver circuit;
• a second bootstrap switch;
• and
• a second bootstrap capacitor coupled to the switch node and to the second bootstrap switch, the second bootstrap capacitor arranged to supply a second power voltage to the pre-driver circuit.

A method of operating a circuit, the method comprising:

• providing a first switch coupled to a second switch at a switch node, wherein the switch node changes between first and second switch node voltages;
• providing a driver circuit coupled to the first switch;
• providing a pre-driver circuit coupled to the driver circuit;
• providing a first bootstrap capacitor coupled to the switch node;
• supplying, by the first bootstrap capacitor, a first power voltage to the driver circuit;
• providing a second bootstrap capacitor coupled to the switch node;
• and
• supplying, by the second bootstrap capacitor, a second power voltage to the pre-driver circuit.