An Adaptive Gate-Side Feedback Active Gate Driver for GaN Devices with Optimized Switching Performance

Area of Science:

• Power Electronics
• Semiconductor Devices

Background:

• Gallium Nitride High Electron Mobility Transistors (GaN HEMT) offer high-frequency performance but suffer from large dV_DS/dt transients.
• These transients lead to crosstalk, current overshoot, and electromagnetic interference (EMI).
• Conventional gate drivers increase switching loss when mitigating these transients.

Purpose of the Study:

• To propose an active gate driver (AGD) that reduces switching loss under dV_DS/dt limitations.
• To adaptively regulate switching transients by providing three-stage driving currents.

Main Methods:

• A gate-side feedback active gate driver (AGD) is proposed.
• Three-stage driving currents are employed, with switching points determined by detecting the Miller plateau start and end.
• Gate driving current during the Miller plateau is reduced to suppress dV_DS/dt and current overshoot.

Main Results:

• The proposed AGD effectively controls dV_DS/dt and suppresses current overshoot under 400 V/20 A conditions.
• The dV_DS/dt-related switching interval was reduced by 68.13%.
• Switching loss was reduced by 51.8%.

Conclusions:

• The proposed active gate driver effectively mitigates dV_DS/dt transients and current overshoot in GaN HEMTs.
• Significant reductions in switching interval and loss confirm the driver's effectiveness for high-frequency applications.