Common-source and common-gate cascade switch device with common-gate current limiting structure

Abstract

The present invention discloses a common-source common-gate cascade switch device with a common-gate current limiting structure, which includes a gate terminal, a source terminal, a drain terminal, a low-voltage enhancement field effect transistor, a high-voltage depletion field effect transistor and a current limiting structure. The current limiting structure includes a plurality of common-gate current limiting depletion field effect transistors and a current limiting resistor. When the switch device is turned on, the current limiting depletion field effect transistor can limit the gate current of the high-voltage depletion field effect transistor through the current limiting resistor and the series internal resistance of the plurality of current limiting depletion field effect transistors, thereby improving the working reliability of the current limiting depletion field effect transistor and the entire switch device.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor manufacturing, and in particular relates to a common-source common-gate cascade type switch device with a common-gate current limiting structure. Background Art

[0002] The common-source and common-gate cascade switching device is composed of a low-voltage enhancement-type field-effect transistor and a high-voltage depletion-type field-effect transistor in a common-source and common-gate manner. Figure 1 It is a common-source and common-gate cascade switching device with a current limiting structure, in which the drain of the high-voltage depletion-type field effect transistor 15 is the drain 13 of the switching device, the gate of the low-voltage enhancement-type field effect transistor 14 is the gate 11 of the switching device, and the source of the low-voltage enhancement-type field effect transistor 14 is the source 12 of the switching device, thereby finally realizing an enhanced function.

[0003] Figure 1 The common-source and common-gate cascade switching device also has a current-limiting depletion-type field effect transistor 16 as a current-limiting structure between the source of the low-voltage enhancement-type field effect transistor 14 and the gate of the high-voltage depletion-type field effect transistor 15. The current-limiting structure can effectively control the size of the turn-on current when the gate voltage of the high-voltage depletion-type field effect transistor 15 changes, thereby stably controlling the turn-on speed of the switching device and improving the control capability of the voltage stress of the secondary-side synchronous tube in the circuit.

[0004] However, when a smaller turn-on current or turn-on speed is required, it is necessary to reduce the absolute value of the threshold voltage of the current limiting depletion type field effect transistor 16, such as reducing the gate dielectric thickness of the current limiting depletion type field effect transistor 16; this will reduce the reliability of the current limiting depletion type field effect transistor 16, and thus affect the reliability of the entire switching device.

[0005] Therefore, it is necessary to provide a common-source and common-gate cascade switch device with a current limiting structure and higher reliability. Summary of the invention

[0006] The present invention aims to solve the above-mentioned problem. The present invention provides a common-source common-gate cascade switch device with a common-gate current limiting structure and high reliability.

[0007] The common-source common-gate cascade switch device with a common-gate current limiting structure comprises:

[0008] A gate terminal, used to receive a voltage signal from a driver;

[0009] A source terminal and a drain terminal, used to form a switch channel of an external load, two semiconductor channels are arranged between the source terminal and the drain terminal;

[0010] A low-voltage enhancement type field effect transistor, wherein the gate of the low-voltage enhancement type field effect transistor serves as the gate terminal of the switching device and is used to receive the voltage signal of the driver; the drain of the low-voltage enhancement type field effect transistor is connected to the source of the high-voltage depletion type field effect transistor, the source of the low-voltage enhancement type field effect transistor serves as the source terminal of the switching device, and the source of the low-voltage enhancement type field effect transistor is connected to the gate of the high-voltage depletion type field effect transistor through a current limiting structure;

[0011] The high-voltage depletion-type field effect transistor, the drain of the high-voltage depletion-type field effect transistor serves as the drain end of the switching device;

[0012] The current limiting structure includes multiple common-gate current limiting depletion type field effect transistors and current limiting resistors, the gate of each current limiting depletion type field effect transistor is connected to the gate of the high-voltage depletion type field effect transistor, the source of the first current limiting depletion type field effect transistor is connected to the gate of the high-voltage depletion type field effect transistor through the current limiting resistor, the drain of the last current limiting depletion type field effect transistor is connected to the source of the low-voltage enhancement type field effect transistor, the source of the nth current limiting depletion type field effect transistor is connected to the drain of the n-1th current limiting depletion type field effect transistor, and n is a positive integer greater than 1.

[0013] In the switch device of this embodiment, the threshold voltage of the current-limiting depletion-type field effect transistor is greater than the threshold voltage of the high-voltage depletion-type field effect transistor.

[0014] In the switch device of this embodiment, the threshold voltages of all current-limiting depletion-type field effect transistors are equal.

[0015] In the switching device of this embodiment, when the switching device is turned on, the gate voltage of the high-voltage depletion-type field effect transistor increases; when the gate voltage of the high-voltage depletion-type field effect transistor is less than the threshold voltage of the first current limiting depletion-type field effect transistor, the gate current of the high-voltage depletion-type field effect transistor is a constant current value.

[0016] In the switching device of this embodiment, the constant current value is determined by the number of the current limiting depletion type field effect transistors, the threshold voltage of the first current limiting depletion type field effect transistor, the source-drain internal resistance of the current limiting depletion type field effect transistor, and the current limiting resistor.

[0017] In the switching device of this embodiment, when the gate voltage of the high-voltage depletion-type field effect transistor is less than the threshold voltage of the first current limiting depletion-type field effect transistor, the gate-source voltage of the n-1th current limiting depletion-type field effect transistor is greater than the gate-source voltage of the nth current limiting depletion-type field effect transistor.

[0018] In the switching device of this embodiment, when the switching device is turned on, the gate voltage of the high-voltage depletion-type field effect transistor increases; when the gate voltage of the high-voltage depletion-type field effect transistor is greater than or equal to the threshold voltage of the current limiting depletion-type field effect transistor, the current limiting depletion-type field effect transistor is in a low resistance state.

[0019] In the switching device of this embodiment, when the switching device is turned off, the gate voltage of the high-voltage depletion-type field effect transistor is greater than or equal to the threshold voltage of the current-limiting depletion-type field effect transistor, and the current-limiting depletion-type field effect transistor is in a low resistance state.

[0020] In the switch device of this embodiment, the structure of the current limiting depletion type field effect transistor includes but is not limited to a metal-oxide semiconductor field effect transistor, a metal-insulator-semiconductor field effect transistor, a metal semiconductor field effect transistor, and a high electron mobility transistor.

[0021] In the switch device of this embodiment, the material of the current limiting depletion type field effect transistor includes but is not limited to gallium nitride, silicon carbide, and silicon.

[0022] Compared with the prior art, the common-source common-gate cascade switching device with a common-gate current limiting structure of the present invention is provided with multiple series-connected current limiting depletion-type field effect transistors and current limiting resistors as the current limiting structure. When the switching device is turned on, the current limiting depletion-type field effect transistor can limit the gate current of the high-voltage depletion-type field effect transistor by the current limiting resistor and the series internal resistance of multiple current limiting depletion-type field effect transistors. That is, the gate current of the high-voltage depletion-type field effect transistor can be reduced by increasing the number of current limiting depletion-type field effect transistors. In this way, the turn-on current of the high-voltage depletion-type field effect transistor can be reduced without changing the threshold voltage of the current limiting depletion-type field effect transistor, thereby improving the working reliability of the current limiting depletion-type field effect transistor and the entire switching device, and effectively solving the technical problem of poor working reliability of the existing common-source common-gate cascade switching device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of a common-source and common-gate cascade type switch device with a current limiting structure;

[0024] Figure 2 It is a structural schematic diagram of a common-source common-gate cascade switch device with a common-gate current limiting structure of the present invention;

[0025] Figure 3 It is a schematic diagram of the change curves of the gate voltage Vg_HEMT1 and the gate current Ig_HEMT1 of the high-voltage depletion-type field effect transistor in the common-source common-gate cascade switch device with a common-gate current limiting structure of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0027] The present invention discloses a common-source common-gate cascade switch device with a common-gate current limiting structure, please refer to Figure 2 , Figure 2 It is a structural schematic diagram of a common-source and common-gate cascade type switch device with a common-gate current limiting structure of the present invention.

[0028] The switch device 20 includes a gate terminal 21, a source terminal 22, a drain terminal 23, a low voltage enhancement type field effect transistor 24, a high voltage depletion type field effect transistor 25 and a current limiting structure 26. The gate terminal 21 is used to receive a voltage signal from a driver; the source terminal 22 and the drain terminal 23 are used to form a switch channel for an external load, and two semiconductor channels (a low voltage enhancement type field effect transistor 24 and a high voltage depletion type field effect transistor 25) are arranged between the source terminal 22 and the drain terminal 23.

[0029] The gate of the low-voltage enhancement type field effect transistor 24 serves as the gate terminal 21 of the switching device 20, and is used to receive the voltage signal of the driver; the drain of the low-voltage enhancement type field effect transistor 24 is connected to the source of the high-voltage depletion type field effect transistor 25, and the source of the low-voltage enhancement type field effect transistor 24 serves as the source terminal 22 of the switching device 20, and the source of the low-voltage enhancement type field effect transistor 24 is connected to the gate of the high-voltage depletion type field effect transistor 25 through the current limiting structure 26; the drain of the high-voltage depletion type field effect transistor 25 serves as the drain terminal 23 of the switching device 20.

[0030] The current limiting structure 26 includes a plurality of common-gate current limiting depletion-type field effect transistors and a current limiting resistor 262, the gate of each current limiting depletion-type field effect transistor is connected to the gate of the high-voltage depletion-type field effect transistor 25, the source of the first current limiting depletion-type field effect transistor 2611 is connected to the gate of the high-voltage depletion-type field effect transistor 25 through the current limiting resistor 262, the drain of the last current limiting depletion-type field effect transistor 261n is connected to the source of the low-voltage enhancement field effect transistor 24, the source of the nth current limiting depletion-type field effect transistor is connected to the drain of the n-1th current limiting depletion-type field effect transistor, wherein n is a positive integer greater than 1. For example, the source of the second current limiting depletion-type field effect transistor 2612 is connected to the drain of the first current limiting depletion-type field effect transistor 2611, and the source of the third current limiting depletion-type field effect transistor 2613 is connected to the drain of the second current limiting depletion-type field effect transistor 2612.

[0031] The threshold voltage of each current limiting depletion type field effect transistor in the switch device of the present invention 20 should be greater than the threshold voltage Vth_HEMT1 of the high voltage depletion type field effect transistor 25. The threshold voltage here refers to the maximum gate voltage of the current limiting depletion type field effect transistor in a high resistance state (this voltage can be adjusted within a certain range).

[0032] Please refer to Figure 1 For example, by reducing the threshold voltage (source-gate threshold voltage) of the current-limiting depletion-type field effect transistor 16, the turn-on current of the switching device can be reduced, and the gate current of the high-voltage depletion-type field effect transistor 15 can be equal to Vth_HEMT2 / R_HEMT2, where Vth_HEMT2 is the threshold voltage of the current-limiting depletion-type field effect transistor, and R_HEMT2 is the gate-source internal resistance of the current-limiting depletion-type field effect transistor.

[0033] However, when the absolute value of the gate voltage of the high-voltage depletion-type field effect transistor 15 is too high, the source-drain voltage of the current-limiting depletion-type field effect transistor 16 will be too large, which may cause the current-limiting depletion-type field effect transistor to break down and affect the working stability of the current-limiting depletion-type field effect transistor and the entire switching device.

[0034] In this embodiment, the threshold voltage of the n-1th current limiting depletion type field effect transistor should be equal to the threshold voltage of the nth current limiting depletion type field effect transistor. Specifically, the threshold voltage of each current limiting depletion type field effect transistor can be set to be the same, or the threshold voltage of the last current limiting depletion type field effect transistor 261n is smaller than the threshold voltage of the previous current limiting depletion type field effect transistor, the threshold voltage of the third current limiting depletion type field effect transistor 2613 is smaller than the threshold voltage of the second current limiting depletion type field effect transistor 2612, the threshold voltage of the second current limiting depletion type field effect transistor 2612 is smaller than the threshold voltage of the first current limiting depletion type field effect transistor 2611, and so on. This arrangement allows the turn-on conditions of all current limiting depletion-type field effect transistors to be met at the same time (when the switch device 20 is turned on, the gate voltage of the current limiting depletion-type field effect transistor is a negative voltage, and the gate-source voltage of the n-1th current limiting depletion-type field effect transistor is greater than the gate-source voltage of the n-1th current limiting depletion-type field effect transistor, or the absolute value of the gate-source voltage of the n-1th current limiting depletion-type field effect transistor is less than the absolute value of the gate-source voltage of the n-1th current limiting depletion-type field effect transistor), facilitating the setting of the current limiting depletion-type field effect transistor.

[0035] When the switch device 20 is turned on, the gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 increases, but the gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 is less than the threshold voltage of each current-limiting depletion-type field effect transistor. Therefore, when the high-voltage depletion-type field effect transistor 25 is turned on, each current-limiting depletion-type field effect transistor is still in a high-resistance state.

[0036] Since the first current limiting depletion type field effect transistor 2611 is provided with a source-drain resistor R_HEMT21, the second current limiting depletion type field effect transistor 2612 is provided with a source-drain resistor R_HEMT22, ... and the last current limiting depletion type field effect transistor 261n is provided with a source-drain resistor R_HEMT2n, the gate-source voltage of each current limiting depletion type field effect transistor is also increasing. Before the gate-source voltage Vgs_HEMT21 of the first current limiting depletion type field effect transistor 2611 reaches the threshold voltage Vth_HEMT21 of the first current limiting depletion type field effect transistor 2611 (the current limiting structure is in a high-resistance state), the gate current Ig_HEMT1 of the high-voltage depletion type field effect transistor 25 is equal to the source-drain leakage current of the last current limiting depletion type field effect transistor 261n, which is approximately equal to Vth_HEMT2n / (R_HEMT21+ R_HEMT22...+ R_HEMT2n+Rg). The gate current is a constant value, which is determined by the threshold voltage Vth_HEMT2n of the last current limiting depletion type field effect transistor 261n, the source-drain internal resistance of other current limiting depletion type field effect transistors, and the resistance Rg of the current limiting resistor 262.

[0037] Since the gate current of the high-voltage depletion-type field effect transistor 25 can be adjusted by the internal resistance of other current-limiting depletion-type field effect transistors, the gate turn-on resistance of the high-voltage depletion-type field effect transistor 25 can be increased by increasing the number of current-limiting depletion-type field effect transistors, thereby controlling the turn-on current at a smaller level, avoiding adjusting the gate dielectric structure of the current-limiting depletion-type field effect transistor, which would affect the reliability of the current-limiting depletion-type field effect transistor or even the entire switching device.

[0038] During the process of turning on the switch device 20, the gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 and the gate current Ig_HEMT1 of the high-voltage depletion-type field effect transistor 25 are shown in FIG. Figure 3 As shown in the figure, it can be seen that when the gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 is less than the threshold voltage Vth_HEMT21 of the first current-limiting depletion-type field effect transistor 2611, the gate current Ig_HEMT1 (turn-on current) of the high-voltage depletion-type field effect transistor 25 is a certain value. At this time, the user can effectively control the turn-on speed of the switch device 20 through the gate current Ig_HEMT1.

[0039] The gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 continues to increase under the discharge effect of the high-voltage depletion-type field effect transistor 25 (the absolute value of the gate voltage gradually approaches zero). When the gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 is greater than or equal to the threshold voltage Vth_HEMT21 of the first current limiting depletion-type field effect transistor 2611, the first current limiting depletion-type field effect transistor 2611 is turned on, and the first current limiting depletion-type field effect transistor 2611 is in a low resistance state. Since the threshold voltages of the other current limiting depletion-type field effect transistors are equal to the threshold voltage of the first current limiting depletion-type field effect transistor 2611, and at this time the n-1th current limiting The gate voltage of the depletion-type field effect transistor is greater than the gate voltage of the nth current limiting depletion-type field effect transistor; when the first current limiting depletion-type field effect transistor 2611 is turned on, the gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 will continue to be applied to the second current limiting depletion-type field effect transistor 2612, the third current limiting depletion-type field effect transistor 2613...the nth current limiting depletion-type field effect transistor 261n, so all subsequent current limiting depletion-type field effect transistors will also be turned on in sequence. At this time, the current limiting depletion-type field effect transistors are in a low resistance state, which effectively avoids the situation where some current limiting depletion-type field effect transistors are still in a high resistance state after some current limiting depletion-type field effect transistors are turned on.

[0040] When the switch device 20 is turned off, the gate voltage Vg_HEMT1 of the high-voltage depletion-type field effect transistor 25 is greater than or equal to the threshold voltage of all current-limiting depletion-type field effect transistors, and all current-limiting depletion-type field effect transistors are in a low resistance state. At this time, the current of the current-limiting depletion-type field effect transistor is the largest, thereby achieving a faster turn-off speed and reducing turn-off loss.

[0041] Since the switching device of the present embodiment mainly generates a constant gate turn-on current through the threshold voltage of the last current limiting depletion type field effect transistor 261n, the source-drain internal resistance of all current limiting depletion type field effect transistors and the current limiting resistor, the failure of one of the current limiting depletion type field effect transistors (such as a short circuit, etc.) will not significantly affect the current limiting effect; if the threshold voltages of all current limiting depletion type field effect transistors are set to be the same, when the last current limiting depletion type field effect transistor 261n fails, any current limiting depletion type field effect transistor can serve as the last current limiting depletion type field effect transistor to provide the necessary threshold voltage.

[0042] Therefore, the switch device 20 in this embodiment can control the turn-on current and thus the turn-on speed through the current limiting depletion type field effect transistor in the turn-on stage, and can adjust the turn-on current by adjusting the number of the current limiting depletion type field effect transistors. In addition, the switch device 20 can achieve a large current in the turn-off stage, thereby achieving a faster turn-off speed and reducing the turn-off loss; thereby improving the working reliability of the current limiting depletion type field effect transistor and the entire switch device.

[0043] The current limiting structure of the switch device of this embodiment can be made by external packaging integration. The structures of the current limiting depletion type field effect transistor and the high voltage depletion type field effect transistor in the current limiting structure include but are not limited to metal-oxide semiconductor field effect transistor (MOSFET, Metal-Oxide-Semiconductor Field Effect Transistor), metal-insulator-semiconductor field effect transistor (MISFET, Metal Insulation Semiconductor Field Effect Transistor), metal semiconductor field effect transistor (MESFET, Metal-Semiconductor Field Effect Transistor), and high electron mobility transistor (HEMT, High Electron Mobility Transistor). The materials of the current limiting depletion type field effect transistor and the high voltage depletion type field effect transistor include but are not limited to gallium nitride, silicon carbide, and silicon.

[0044] The above-mentioned current limiting depletion type field effect transistor can be integrated with the high-voltage depletion type field effect transistor in the same chip, and can also be integrated with the low-voltage enhancement type field effect transistor in the same chip. Furthermore, the current limiting depletion type field effect transistor, the high-voltage depletion type field effect transistor and the low-voltage enhancement type field effect transistor can also be set as one device through packaging.

[0045] The common-source common-gate cascade switch device with a common-gate current limiting structure of the present invention is provided with a plurality of current-limiting depletion-type field effect tubes and a current-limiting resistor connected in series as a current-limiting structure. When the switch device is turned on, the current-limiting depletion-type field effect tube can limit the turn-on current by the current-limiting resistor and the series internal resistance of the plurality of current-limiting depletion-type field effect tubes, that is, the gate turn-on current of the high-voltage depletion-type field effect tube can be reduced by increasing the number of the current-limiting depletion-type field effect tubes. In this way, the turn-on current of the high-voltage depletion-type field effect tube can be reduced without changing the threshold voltage of the current-limiting depletion-type field effect tube, thereby improving the working reliability of the current-limiting depletion-type field effect tube and the entire switch device, and effectively solving the technical problem of poor working reliability of the existing common-source common-gate cascade switch device.

[0046] Although the present invention is disclosed through the above embodiments, the protection scope of the present invention is not limited thereto. Without departing from the concept of the present invention, several deductions and replacements of the above components will fall within the scope of the claims of the present invention.

Claims

1. A common-source common-gate cascade switch device with a common-gate current limiting structure, characterized in that: include: A gate terminal, used to receive a voltage signal from a driver; A source terminal and a drain terminal, used to form a switch channel of an external load, two semiconductor channels are arranged between the source terminal and the drain terminal; A low voltage enhancement type field effect transistor, wherein the gate of the low voltage enhancement type field effect transistor serves as the gate terminal of the switching device and is used to receive a voltage signal from a driver; The drain of the low voltage enhancement type field effect transistor is connected to the source of the high voltage depletion type field effect transistor, the source of the low voltage enhancement type field effect transistor serves as the source terminal of the switch device, and the source of the low voltage enhancement type field effect transistor is connected to the gate of the high voltage depletion type field effect transistor through a current limiting structure; The high-voltage depletion-type field effect transistor, the drain of the high-voltage depletion-type field effect transistor serves as the drain end of the switching device; The current limiting structure comprises a plurality of common-gate current limiting depletion-type field effect transistors and a current limiting resistor, the gate of each current limiting depletion-type field effect transistor is connected to the gate of the high-voltage depletion-type field effect transistor, the source of the first current limiting depletion-type field effect transistor is connected to the gate of the high-voltage depletion-type field effect transistor through the current limiting resistor, the source of the nth current limiting depletion-type field effect transistor is connected to the drain of the n-1th current limiting depletion-type field effect transistor, wherein n is a positive integer greater than 1; and the drain of the last current limiting depletion-type field effect transistor is connected to the source of the low-voltage enhancement-type field effect transistor; When the switch device is turned on, the gate voltage of the high-voltage depletion-type field effect transistor increases; when the gate voltage of the high-voltage depletion-type field effect transistor is less than the threshold voltage of the first current-limiting depletion-type field effect transistor, the gate current of the high-voltage depletion-type field effect transistor is a constant current value; The constant current value is determined by the number of the current limiting depletion type field effect transistors, the threshold voltage of the last current limiting depletion type field effect transistor, the source-drain internal resistance of the current limiting depletion type field effect transistor, and the current limiting resistor; When the gate voltage of the high-voltage depletion-type field effect transistor is less than the threshold voltage of the first current limiting depletion-type field effect transistor, the gate-source voltage of the n-1th current limiting depletion-type field effect transistor is greater than the gate-source voltage of the nth current limiting depletion-type field effect transistor.

2. The common-source common-gate cascade switch device with a common-gate current limiting structure according to claim 1, characterized in that: The threshold voltage of the current limiting depletion type field effect transistor is greater than the threshold voltage of the high voltage depletion type field effect transistor.

3. The common-source common-gate cascade switch device with a common-gate current limiting structure according to claim 2, characterized in that: The threshold voltages of all current limiting depletion-type field effect transistors are equal.

4. The common-source common-gate cascade switch device with a common-gate current limiting structure according to claim 3, characterized in that: When the switch device is turned on, the gate voltage of the high-voltage depletion-type field effect transistor increases; when the gate voltage of the high-voltage depletion-type field effect transistor is greater than or equal to the threshold voltage of the current limiting depletion-type field effect transistor, the current limiting depletion-type field effect transistor is in a low resistance state.

5. The common-source common-gate cascade switch device with a common-gate current limiting structure according to claim 3, characterized in that: When the switch device is turned off, the gate voltage of the high-voltage depletion-type field effect transistor is greater than or equal to the threshold voltage of the current-limiting depletion-type field effect transistor, and the current-limiting depletion-type field effect transistor is in a low resistance state.

6. The common-source common-gate cascade switch device with a common-gate current limiting structure according to claim 1, characterized in that: The structures of the current-limiting depletion-type field effect transistor and the high-voltage depletion-type field effect transistor include but are not limited to metal-oxide semiconductor field effect transistors, metal-insulator-semiconductor field effect transistors, metal semiconductor field effect transistors, and high electron mobility transistors.

7. The common-source common-gate cascade switch device with a common-gate current limiting structure according to claim 1, characterized in that: The materials of the current limiting depletion mode field effect transistor and the high voltage depletion mode field effect transistor include but are not limited to gallium nitride, silicon carbide, and silicon.

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