Gallium nitride power tube driving circuit with overcurrent protection function

Abstract

The invention discloses a gallium nitride power tube driving circuit with an overcurrent protection function, which comprises a first under-voltage detection module, a low-dropout voltage stabilizing circuit, a second under-voltage detection module, a first level conversion module, an overcurrent detection module, an input module, a logic control module, a second level conversion module and a driving module, the over-current detection module is connected with the logic control module, the logic control module is connected with the second level conversion module, the second level conversion module is connected with the driving module, and current flowing through the gallium nitride power tube generates sampling voltage on the current sampling resistor R1. When a GaN power tube is over-current, the voltage of the PGND is higher than a preset threshold voltage of the over-current detection module, the over-current detection module outputs a high level after over-current is maintained for a certain time, the OUT pin is set to be a low level through the logic control module, and the GaN power tube over-current protection circuit is simple in structure and can provide an over-current protection function of the GaN power tube.

Description

technical field [0001] The invention belongs to the field of analog integrated circuit design, and in particular relates to a gallium nitride power tube drive circuit with an overcurrent protection function. Background technique [0002] Gallium nitride (GaN) power tube has the characteristics of wide band gap, strong atomic bond, high thermal conductivity, stable chemical performance, strong radiation resistance, similar structure to wurtzite, and high hardness. It is used in optoelectronics, high-temperature high-power devices and High-frequency microwave devices and other aspects have been widely used. The usual gallium nitride power transistor is a depletion device, that is, when the gate-source voltage is 0V, the power transistor is still turned on. Only when the gate-source voltage is negative and lower than the threshold voltage of the gallium nitride power transistor, the power transistor Therefore, the scheme of directly driving the gate of GaN power transistor is ...

AI Technical Summary

Problems solved by technology

[0003] If you want to sample the current of the GaN power tube and perform over-current protection, you need to figure 1 The S port of the combination device is connected in series with the current sampling resistor to the ground. When the current changes, the voltage of the S port will change greatly. It is very likely that the gate-source driving voltage of the low-voltage MOSFET power tube is insufficient, or the safe driving voltage is exceeded.

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