CN216873068U

CN216873068U - Driving and current detection circuit of D-Mode gallium nitride power tube easy to integrate

Info

Publication number: CN216873068U
Application number: CN202221327983.6U
Authority: CN
Inventors: 江辉华; 甘戈; 李瑛�; 吴小虎
Original assignee: Yutai Semiconductor Co ltd
Current assignee: Yutai Semiconductor Co ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-07-01
Anticipated expiration: 2032-05-31

Abstract

The utility model provides an easy-to-integrate driving and current detection circuit of a D-Mode gallium nitride power tube, which comprises a D-Mode gallium nitride power tube and a first normally-closed power tube connected with the D-Mode gallium nitride power tube in series, wherein a grid electrode of the D-Mode gallium nitride power tube is connected with a source electrode of the first normally-closed power tube, a source electrode of the D-Mode gallium nitride power tube is connected with a drain electrode of the first normally-closed power tube, a grid electrode of the first normally-closed power tube is a driving signal input end, and a drain electrode of the D-Mode gallium nitride power tube is a switch connection end. The utility model converts the D-Mode gallium nitride power tube which is difficult to control into the silicon LD MOS which is easy to control for control, the control is simple, and simultaneously, the driving voltage range of the grid is greatly widened; the first normally-closed power tube and the second normally-closed power tube which are current mirrors can be integrated into a chip to form a driving chip of the D-Mode gallium nitride power tube, so that the system integration level is improved; and a main circuit current detection resistor is omitted, and the main circuit resistance loss is reduced.

Description

Driving and current detection circuit of D-Mode gallium nitride power tube easy to integrate

Technical Field

The utility model relates to the technical field of electronic circuits, in particular to a driving and current detection circuit of a D-Mode gallium nitride power tube easy to integrate.

Background

A third generation semiconductor GaN power transistor, a High Electron Mobility Transistor (HEMT), has a critical electric field strength greater than that of silicon, and the size of GaN is smaller for the same on-chip resistance and breakdown voltage. GaN also has extremely fast switching speed and excellent reverse recovery performance, its on-resistance is very low, which makes its static power consumption significantly reduced, and its input capacitance is very low, has improved switching speed, and then makes GaN power tube specially adapted to low-loss, high-efficiency occasion.

The GaN power tube is divided into two types of E-Mode (enhancement Mode) and D-Mode (depletion Mode), wherein the GaN power tube of the E-Mode has characteristics similar to a silicon NMOS transistor, is normally cut off, a positive voltage must be added between a grid source in order to turn on the GaN power tube, but the on driving voltage is low and the range is small, and in addition, a zero voltage or even a negative voltage must be added between the grid source to turn off the GaN power tube, so that the requirement on a driving circuit is high; the GaN power tube of the D-Mode is conducted in a normal state, a negative voltage must be added between a grid source and a grid source when the GaN power tube of the D-Mode is started to cut off a device so as to avoid short-circuit current generated in the starting process, the GaN power tube is not electrified in the normal state, and a circuit is always in an unsafe state in the normally open state, so that the GaN power tube of the D-Mode is not an ideal stable system.

It is a common technique to control the turn-on and turn-off of a normally-on transistor device by forming a composite circuit of the normally-on transistor device and the normally-off transistor device connected in series. If the application number is: 201310552596.1 which discloses a switching circuit comprising a first transistor device 2 and a second transistor device 3, as shown in fig. 1. The first transistor device 2 and the second transistor device 3 both have a load path and a control terminal. The load paths of the first transistor device 2 and the second transistor device 3 are connected in series. The control terminal of the first transistor device 2 is configured to receive a first drive signal and the control terminal of the second transistor device 3 is configured to receive a second drive signal. The first transistor device 2 comprises a load path and control terminal 23 between a first load terminal 21 and a second load terminal 22, and the second transistor device 3 comprises a load path and control terminal 33 between a first load terminal 31 and a second load terminal 32. The load paths of the first transistor device 2 and the second transistor device 3 are connected in series by coupling the first load terminal 31 of the second transistor device 3 to the second load terminal 22 of the first transistor device 2. The first transistor device 2 is a normally off transistor and the second transistor device 3 is a normally on transistor. The switching circuit realizes the functions through 2 control signals, the control process is complex, an external main circuit current detection resistor is needed, and the loss of the main circuit resistor is large.

SUMMERY OF THE UTILITY MODEL

In order to solve at least one of the above technical problems, the present invention provides a driving and current detecting circuit of a D-Mode gan power transistor, which is easy to integrate.

A driving and current detection circuit of a D-Mode gallium nitride power tube easy to integrate comprises the D-Mode gallium nitride power tube and a first normally-closed power tube connected with the D-Mode gallium nitride power tube in series, wherein a grid electrode of the D-Mode gallium nitride power tube is connected with a source electrode of the first normally-closed power tube, a source electrode of the D-Mode gallium nitride power tube is connected with a drain electrode of the first normally-closed power tube, the grid electrode of the first normally-closed power tube is a driving signal input end, and the drain electrode of the D-Mode gallium nitride power tube is a switch connection end.

Preferably, the easy-to-integrate D-Mode gan power transistor driving and current detecting circuit further includes a second normally-off power transistor that is a current mirror image of the first normally-off power transistor, that is, a gate of the first normally-off power transistor is connected to a gate of the second normally-off power transistor, a source of the first normally-off power transistor is connected to a source of the second normally-off power transistor, and a drain of the first normally-off power transistor is connected to a drain of the second normally-off power transistor.

In any of the above embodiments, the driving and current detecting circuit of the D-Mode gan power transistor, which is easy to integrate, further includes a resistor, one end of the resistor is connected to the source of the second normally-off power transistor, and the other end of the resistor is connected to the source of the first normally-off power transistor.

In any of the above embodiments, preferably, the source of the first normally-off power transistor is grounded.

In any of the above embodiments, preferably, the first normally-off power transistor and the second normally-off power transistor are silicon LD MOS (crystal Double-diffused MOSFET).

Preferably, in any of the above schemes, the resistance has a value range of 10 Ω -1M Ω.

In any of the above embodiments, preferably, the first normally-off power transistor and the second normally-off power transistor are integrated into a driver chip.

Preferably, in any of the above schemes, the driving chip further integrates a driving amplifier, and an output end of the driving amplifier is connected to the driving signal input end.

Preferably, in any of the above schemes, the driving chip further integrates a PWM generator, and an output terminal of the PWM generator is connected to an input terminal of the driving amplifier.

The easy-to-integrate driving and current detection circuit of the D-Mode gallium nitride power tube has the following beneficial effects:

the D-Mode gallium nitride power tube which is difficult to control is converted into the silicon LD MOS which is easy to control for control, the control is simple, and the driving voltage range of the grid electrode is greatly widened;

the first normally-closed power tube and the second normally-closed power tube which are current mirrors can be integrated into a chip to form a driving chip of the D-Mode gallium nitride power tube, so that the design difficulty of the chip is reduced, the integration level of a system is improved, an application circuit is simplified, and the difficulty of mass production is reduced;

the main circuit current detection resistor is omitted, and the current of the second normally-closed functional tube and the resistor connected in series with the second normally-closed functional tube is set according to the mirror image ratio, so that the main circuit resistance loss is reduced, and the current is controllable.

Drawings

Fig. 1 is a schematic diagram of a switch circuit disclosed in the prior art.

Fig. 2 is a schematic diagram of a preferred embodiment of a driving and current sensing circuit for a D-Mode gan power transistor that is easily integrated according to the present invention.

Fig. 3 is a schematic diagram of another embodiment of a driving and current detecting circuit of a D-Mode gan power transistor that can be easily integrated according to the present invention.

FIG. 4 is a schematic diagram of the driving and current detecting circuit of the D-Mode GaN power transistor of the present invention, as shown in FIG. 3.

FIG. 5 is a schematic diagram of another application of the driving and current detecting circuit of the D-Mode GaN power transistor of the utility model, as shown in FIG. 3.

FIG. 6 is a schematic diagram of a driving and current detecting circuit of a D-Mode GaN power transistor easy to integrate according to another embodiment of the utility model.

Detailed Description

For a better understanding of the present invention, reference will now be made in detail to the following examples.

Example 1

As shown in fig. 2, an easily integrated driving and current detecting circuit for a D-Mode gan power transistor includes a D-Mode gan power transistor Q1 and a first normally-closed power transistor Q2 connected in series with the D-Mode gan power transistor Q1, a gate of the D-Mode gan power transistor Q1 is connected to a source of the first normally-closed power transistor Q2, a source of the D-Mode gan power transistor Q1 is connected to a drain of the first normally-closed power transistor Q2, a gate of the first normally-closed power transistor Q2 is a driving signal input terminal, and a drain of the D-Mode gan power transistor Q1 is a switch connection terminal.

In this embodiment, the easy-to-integrate D-Mode gan power transistor driving and current detecting circuit further includes a second normally-off power transistor Q3 that is a current mirror image of the first normally-off power transistor Q2, i.e., the gate of the first normally-off power transistor Q2 is connected to the gate of the second normally-off power transistor Q3, the source of the first normally-off power transistor Q2 is connected to the source of the second normally-off power transistor Q3, and the drain of the first normally-off power transistor Q2 is connected to the drain of the second normally-off power transistor Q3. The first normally-off power transistor Q2 and the second normally-off power transistor Q3 are silicon LD MOS (Lateral Double-diffused MOSFET). The source of the first normally-off power transistor Q2 is grounded.

In this embodiment, it is preferable that the driving and current detecting circuit of the D-Mode gan power transistor easy to integrate further includes a resistor Rcs, one end of the resistor Rcs is connected to the source of the second normally-off power transistor Q3, and the other end of the resistor Rcs is connected to the source of the first normally-off power transistor Q2. The value range of the resistor Rcs is 10 Ω -1M Ω.

The gate of the control end of the normally-open D-Mode gallium nitride power tube Q1 is connected with the source of the normally-closed first normally-closed power tube Q2, so that when Q2 is conducted, the source voltage of Q1 is pulled down to be the same as the gate voltage of the Q1, and Q1 enters a conducting state; when the Q2 is disconnected, the source of the Q1 is disconnected, even if the gate of the Q1 is connected with the source of the Q2, the Q1 is in a disconnected state because the source of the Q1 is floating, and the voltage of the drain of the Q2 is limited within a range because the gate of the Q1 is connected with the source of the Q2, so that the Q1 switch is controlled by the Q2 switch, the D-Mode gallium nitride power tube Q1 which is difficult to control is converted into the silicon LD MOS Q2 which is easy to control, the control is simple, and the control of the D-Mode gallium nitride power tube Q1 can be realized only by a conventional control signal. Meanwhile, the switching rate of the silicon LD MOS reaches several M levels, and for a switching circuit with the switching rate requirement of only several hundred K levels, the switching rate performance requirement of the whole switching circuit cannot be influenced by adopting the silicon LD MOS to control the D-Mode gallium nitride power tube.

The mirror current ratio between the first normally-closed power transistor Q2 and the second normally-closed power transistor Q3 is k, that is, if the maximum allowable current of the second normally-closed power transistor Q3 is I, the maximum allowable current of the first normally-closed power transistor Q2 is kI, and further the maximum allowable current of the D-Mode gallium nitride power transistor Q1 is (1 + k) I. The maximum allowable current I of the k and the second normally-closed power tube Q3 is set by adjusting the resistance value of the resistor Rcs according to requirements, and the large allowable current of the Q3 is usually set to be much smaller than that of the Q2, generally more than 10 times, that is, the value of k is greater than 10. In this embodiment, it is preferable that the value of k is 1000, the maximum allowable current of the second normally-closed power tube Q3 is 1mA, the maximum allowable current of the first normally-closed power tube Q2 is 1A, and the maximum allowable current of the D-Mode gallium nitride power tube Q1 is 1.001A ≈ 1A. The current detection control function is realized through a second normally-closed power tube Q3 which is arranged in a mirror image mode with the first normally-closed power tube Q2 and a resistor Rcs which is connected with the second normally-closed power tube Q3 in series, the current sizes of Q1, Q2 and Q3 are set through the second normally-closed power tube Q3 and the resistor Rcs which is connected with the second normally-closed power tube Q3 in series according to a mirror image ratio, compared with a mode that a main circuit current detection resistor is arranged and voltage on the main circuit current detection resistor is directly detected to detect current, the main circuit current detection resistor is omitted, and the main circuit resistance loss is reduced.

Example 2

As shown in fig. 3, in this embodiment, it is preferable that the first normally-closed power transistor Q2 and the second normally-closed power transistor Q3 are integrated into a driving chip, a driving amplifier is further integrated into the driving chip, an output terminal of the driving amplifier is connected to the driving signal input terminal, and an input terminal of the driving amplifier is externally connected to a PWM generator. In this embodiment, it is preferable that the PWM generator uses an existing PWM generator chip. The first normally-closed power tube Q2 and the second normally-closed power tube Q3 which are current mirrors can be integrated into a chip to form a driving chip of the D-Mode gallium nitride power tube Q1, so that the design difficulty of the chip is reduced, the system integration level is improved, an application circuit is simplified, and the difficulty of mass production is reduced.

Example 3

As shown in fig. 4, the driving and current detecting circuit of the D-Mode gan power transistor, which is easy to integrate, is applied to a single-ended flyback DC-DC converter, and the D-Mode gan power transistor Q1 is used as a switching transistor of the single-ended flyback DC-DC converter.

Example 4

As shown in fig. 5, the driving and current detecting circuit of the D-Mode gan power transistor easy to integrate is applied to a PFC power factor (Boost type) correction circuit, and the D-Mode gan power transistor Q1 is used as a switching transistor of the PFC power factor (Boost type) correction circuit.

Example 5

Unlike embodiment 2, as shown in fig. 6, a PWM generator is further integrated in the driving chip, and an output terminal of the PWM generator is connected to an input terminal of the driving amplifier.

It should be noted that, the technical solution of the present application is designed to be an improvement in hardware, and does not relate to an improvement in software; for each part without the indicated model, the part can be selected from common parts in the prior art and is not limited by the model; the components of the embodiments are indicated by the models, which are only used for describing the technical scheme of the application in detail, and it should be understood that the technical scheme to be protected by the utility model is not limited by the models, and the prior art has many alternatives for replacing the components.

The above examples are only for illustrating the technical solutions of the present invention, and not for limiting the same; although the foregoing embodiments illustrate the utility model in detail, those skilled in the art will appreciate that: it is possible to modify the technical solutions described in the foregoing embodiments or to substitute some or all of the technical features thereof, without departing from the scope of the technical solutions of the present invention.

Claims

1. A driving and current detection circuit of a D-Mode gallium nitride power tube easy to integrate comprises the D-Mode gallium nitride power tube and a first normally-closed power tube connected with the D-Mode gallium nitride power tube in series, and is characterized in that: the grid electrode of the D-Mode gallium nitride power tube is connected with the source electrode of the first normally-closed power tube, the source electrode of the D-Mode gallium nitride power tube is connected with the drain electrode of the first normally-closed power tube, the grid electrode of the first normally-closed power tube is a driving signal input end, and the drain electrode of the D-Mode gallium nitride power tube is a switch connection end.

2. The easy-to-integrate D-Mode gan power transistor driving and current detecting circuit as claimed in claim 1, wherein: the power supply circuit further comprises a second normally-closed power tube which is in a current mirror image with the first normally-closed power tube, namely the grid electrode of the first normally-closed power tube is connected with the grid electrode of the second normally-closed power tube, the source electrode of the first normally-closed power tube is connected with the source electrode of the second normally-closed power tube, and the drain electrode of the first normally-closed power tube is connected with the drain electrode of the second normally-closed power tube.

3. The easy-to-integrate D-Mode gan power transistor driving and current detecting circuit as claimed in claim 2, wherein: the power supply circuit further comprises a resistor, wherein one end of the resistor is connected to the source electrode of the second normally-closed power tube, and the other end of the resistor is connected to the source electrode of the first normally-closed power tube.

4. The easy-to-integrate D-Mode gan power transistor driving and current detecting circuit as claimed in claim 3, wherein: the source electrode of the first normally-off power tube is grounded.

5. The easy-to-integrate D-Mode gan power transistor driving and current detecting circuit as claimed in claim 2, wherein: the first normally-closed power tube and the second normally-closed power tube are silicon LD MOS.

6. The easy-to-integrate D-Mode gan power transistor driving and current detecting circuit as claimed in claim 3, wherein: the resistance value range is 10 Ω -1M Ω.

7. The easy-to-integrate D-Mode gan power transistor driving and current sensing circuit as claimed in claim 5, wherein: the first normally-off power tube and the second normally-off power tube are integrated into a driving chip.

8. The easy-to-integrate D-Mode gan power transistor driving and current detecting circuit as claimed in claim 7, wherein: the driving chip is further integrated with a driving amplifier, and the output end of the driving amplifier is connected with the driving signal input end.

9. The easy-to-integrate D-Mode gan power transistor driving and current detecting circuit as claimed in claim 8, wherein: the driving chip is further integrated with a PWM generator, and the output end of the PWM generator is connected with the input end of the driving amplifier.