Design Considerations of Bootstrap Gate Driver With Fault Mitigation for Si- and GaN-Based High-Current Converters

The bootstrap gate driver circuits are widely used for bridge-arm-type high-current and high-power-density converters due to their low cost and compact structures. In high-current applications, improper bootstrap parameters and circuit design will cause start-up gate–source voltage oscillation, bridge-arm shoot-through, and gate–source voltage overshoot. Because of the lack of research and detailed model on the above three aspects in high-current applications, this article proposes a full-parameter model of the driver circuit through a detailed analysis of the driver circuit and summarizes a set of systematic design methods, which provides a reference for the parameters and circuit design of bootstrap gate driver for Si-based or GaN-based converters. This article will help tackle the challenges encountered in the bootstrap gate driver circuit design for high-current and high-power-density converters.