Isolated gate-driver bias-supply design considerations

Electric and hybrid-electric vehicles are the future of the automotive industry. As a result, the use of automotive inverters and on-board chargers is driving the need to use wide bandgap devices (i.e., SiC, GaN), isolated gate drivers and isolated gate-driver bias supply. Even though the gate-driver bias supply is a small portion of the entire design, it affects the reliability of the gate driver, overall system efficiency and the system electromagnetic interference (EMI). This presentation examines gate-driver bias-supply architecture requirements and solutions that consider reliability, performance, low-EMI and BOM reduction using LLC converters and flyback converters as an example.