Switched-mode DC/DC converter having a bootstrapped high-side driver

摘要

A gate driver for a high-side NMOS power transistor in a DC/DC boost converter includes first and second switches coupled in series between an output pin and the gate of the high-side transistor. A third switch is coupled between the gate and a switch-node between the high-side and low-side transistors, the switch node also being coupled to an input pin. Fourth and fifth switches are coupled in series between the output pin and a clamp pin. Sixth and seventh switch are coupled in series between the output pin and a ground pin. First and second bootstrap capacitors have respective first terminals coupled to a first node between the first and second switches. The first capacitor has a second terminal coupled to a node between the fourth and fifth switches; the second capacitor has a second terminal coupled to a node between the sixth and seventh switches.