eGaN HEMT bridge arm crosstalk suppression driving circuit and control method thereof

Abstract

The invention discloses an eGaN HEMT bridge arm crosstalk suppression driving circuit and a control method thereof. The circuit comprises a first driving circuit connected between a first power supplyand an upper tube of an upper bridge arm, and a second driving circuit connected between a second power supply and a lower tube of a lower bridge arm, the first driving circuit and the second drivingcircuit have the same structure, and each comprises a grid voltage totem pole structure circuit and a low impedance bridge arm crosstalk suppression circuit, wherein the input terminals of the grid voltage totem pole structure circuits are connected to the first power supply or the second power supply, and the output terminals are connected to the grid of the upper tube or the grid of the lower tube; the input terminals of the low impedance bridge crosstalk suppression circuits are connected to the first power supply or the second power supply, and the output terminals are connected to the grid and the source of the upper tube or the grid and the source of the lower tube respectively. The driving circuit can fully utilize the performance advantages of an eGaN HEMT high-speed switch, and realize high-speed switching while fulfilling a bridge crosstalk suppression function.

Description

technical field [0001] The invention relates to a power electronic technology and an electrotechnical circuit and a control method thereof, in particular to an eGaN HEMT bridge arm crosstalk suppression driving circuit and a control method thereof. Background technique [0002] As one of the representative devices of new wide-bandgap semiconductors, gallium nitride (GaN) devices have device advantages such as lower on-resistance, faster switching speed and higher junction temperature working capability than Si devices. As a power device for making converters, Si devices are expected to significantly improve the maximum operating frequency and efficiency of the converters, and reduce their volume and weight. [0003] The bridge arm circuit is a commonly used circuit structure in GaN-based converters, and contains two switching devices that are connected in series with each other and conduct complementary conduction. The high-speed switching behavior of GaN power devices will...

AI Technical Summary

Problems solved by technology

When a switch is turned on, it will cause a forward crosstalk voltage on the gate-source of another switch in the same bridge arm. Since the threshold voltage of GaN devices is much smaller than that of Si devices with the same rating, it is very easy to cause false conduction. , causing the bridge arm to pass through, affecting safe operation; similarly, when a switch is turned off, it will cause a negative crosstalk voltage on the gate-source of another switch in the same bridge arm, which may exceed the gate-source voltage of the GaN device Withstand the range, accelerate the degradation of device performance, and even cause device damage

[0004] In the current literature, aiming at the bridge arm crosstalk problem in the application of GaN-based bridge arm circuits, it is proposed to connect an external capacitor in parallel between the gate and source of the power tube, increase the negative bias voltage at the gate source of the power tube during shutdown, and use active Miller Clamping and other methods, but these methods have the disadvantages of reducing switching speed, increasing switching loss, driving loss, and inability to suppress negative crosstalk voltage, and their practical application value is limited.

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