阅读说明：本技术 一种功放栅压切换装置 (Power amplifier grid voltage switching device ) 是由 陈健 李勇军 周金龙 于 2020-12-03 设计创作，主要内容包括：本发明提供了一种功放栅压切换装置,包括控制器、负电源电路和GaN功率放大器,还包括负电压开关电路,负电压开关电路的常开输入端口与控制器的输出端连接,负电压开关电路的常闭输入端口与负电源电路连接,负电压开关电路的输出端口分别与负电源电路、GaN功率放大器的栅极连接；负电压开关电路用于接收TDD开关信号,并在TDD开关信号为低电平时接通常闭输入端口和输出端口以将负电源电路输出的负电压施加到GaN功率放大器的栅极,从而实现关闭GaN功率放大器,以及在TDD开关信号为高电平时接通常开输入端口和输出端口以将控制器输出的负电压施加到GaN功率放大器的栅极,从而实现打开GaN功率放大器。本发明简单可靠,成本低。(The invention provides a power amplifier grid voltage switching device, which comprises a controller, a negative power supply circuit, a GaN power amplifier and a negative voltage switch circuit, wherein a normally open input port of the negative voltage switch circuit is connected with an output end of the controller; the negative voltage switch circuit is used for receiving the TDD switch signal, and switching on the normally closed input port and the output port when the TDD switch signal is at a low level so as to apply the negative voltage output by the negative power supply circuit to the grid electrode of the GaN power amplifier, thereby realizing the closing of the GaN power amplifier, and switching on the normally open input port and the output port when the TDD switch signal is at a high level so as to apply the negative voltage output by the controller to the grid electrode of the GaN power amplifier, thereby realizing the opening of the GaN power amplifier. The invention is simple and reliable, and has low cost.)

1. A power amplifier grid voltage switching device comprises a controller, a negative power supply circuit and a GaN power amplifier, and is characterized by further comprising a negative voltage switch circuit, wherein the negative power supply circuit is used for supplying power to a negative power supply of the controller and the negative voltage switch circuit; the normally open input port of the negative voltage switch circuit is connected with the output end of the controller, the normally closed input port of the negative voltage switch circuit is connected with the negative power supply circuit, and the output port of the negative voltage switch circuit is respectively connected with the negative power supply circuit and the grid electrode of the GaN power amplifier;

the negative voltage switch circuit is used for receiving a TDD switch signal, and switching on the normally closed input port and the output port to apply the negative voltage output by the negative power supply circuit to the grid electrode of the GaN power amplifier when the TDD switch signal is at a low level so as to close the GaN power amplifier, and switching on the normally open input port and the output port to apply the negative voltage output by the controller to the grid electrode of the GaN power amplifier when the TDD switch signal is at a high level so as to open the GaN power amplifier.

2. The power amplifier grid voltage switching device according to claim 1, further comprising a first filter circuit connected between the output terminal of the controller and the normally open input port of the negative voltage switch circuit for filtering the negative voltage outputted by the controller.

3. The power amplifier grid voltage switching device according to claim 2, wherein the first filter circuit comprises a first capacitor and a second capacitor connected in parallel between the output terminal of the controller and the normally open input port of the negative voltage switch circuit, and the first capacitor and the second capacitor are respectively grounded.

4. The power amplifier gate voltage switching device of claim 1, further comprising a temperature compensation circuit, connected to the output of the controller, for canceling a current variation of the gate quiescent current of the GaN power amplifier due to a temperature variation, so as to keep the gate quiescent current constant.

5. The power amplifier grid voltage switching device according to claim 4, wherein the temperature compensation circuit comprises a diode and a first resistor connected in series in sequence, the diode is grounded, and the first resistor is connected with the output end of the controller.

6. The power amplifier grid voltage switching device of claim 1, further comprising a second filter circuit connected between the negative power circuit and the normally closed input port of the negative voltage switch circuit for filtering the negative voltage output by the negative power circuit.

7. The power amplifier grid voltage switching device according to claim 1, further comprising an overshoot cancellation circuit connected between the output port of the negative voltage switch circuit and the gate of the GaN power amplifier for canceling an overshoot interference signal and a ringing signal in the negative voltage output by the negative voltage switch circuit.

8. The device of claim 7, further comprising a third filter circuit, connected between the overshoot elimination circuit and the gate of the GaN power amplifier, for filtering the negative voltage output by the overshoot elimination circuit.

9. The power amplifier gate voltage switching device of claim 1, wherein an output port of the negative voltage switch circuit is connected to the negative power supply circuit through a second resistor.

10. The power amplifier grid voltage switching device according to claim 1, further comprising a drain power switch circuit connected to the controller and the drain of the GaN power amplifier, wherein the controller is configured to output a drain power switch signal to the drain power switch circuit, and the drain power switch circuit is configured to receive the drain switch signal output by the controller to implement switching control when the drain of the GaN power amplifier is powered.

[ technical field ] A method for producing a semiconductor device

The invention relates to the technical field of radio frequency, in particular to a power amplifier grid voltage switching device.

[ background of the invention ]

GaN (gallium nitride)) power amplifiers, which are depletion transistor devices, are used at the base station side, and compared with 4G and 5G communication bands, GaN power amplifiers are shifted to high frequency bands, and can effectively meet the requirements of 5G such as high power, high communication band and high efficiency.

At present, in a Time Division Duplex (TDD) system, a circuit for controlling a GaN power amplifier to switch between off and on is complex.

Therefore, it is desirable to provide a simple and reliable apparatus that can control the switching of a GaN power amplifier between off and on.

[ summary of the invention ]

The invention mainly aims to provide a power amplifier grid voltage switching device which can control a GaN power amplifier to switch between closing and opening, and is simple and reliable.

In order to achieve the above object, the present invention provides a power amplifier grid voltage switching device, which comprises a controller, a negative power circuit, a GaN power amplifier, and a negative voltage switch circuit, wherein the negative power circuit is used for supplying power to a negative power of the controller and the negative voltage switch circuit; the normally open input port of the negative voltage switch circuit is connected with the output end of the controller, the normally closed input port of the negative voltage switch circuit is connected with the negative power supply circuit, and the output port of the negative voltage switch circuit is respectively connected with the negative power supply circuit and the grid electrode of the GaN power amplifier; the negative voltage switch circuit is used for receiving a TDD switch signal, and switching on the normally closed input port and the output port to apply the negative voltage output by the negative power supply circuit to the grid electrode of the GaN power amplifier when the TDD switch signal is at a low level so as to close the GaN power amplifier, and switching on the normally open input port and the output port to apply the negative voltage output by the controller to the grid electrode of the GaN power amplifier when the TDD switch signal is at a high level so as to open the GaN power amplifier.

As a preferable technical solution, the controller further comprises a first filter circuit, wherein the first filter circuit is connected between the output end of the controller and the normally open input port of the negative voltage switch circuit, and is used for filtering the negative voltage output by the controller.

As a preferred technical solution, the first filter circuit includes a first capacitor and a second capacitor connected in parallel between the output terminal of the controller and the normally open input port of the negative voltage switch circuit, and the first capacitor and the second capacitor are grounded, respectively.

As a preferred technical solution, the GaN power amplifier further comprises a temperature compensation circuit, connected to the output end of the controller, for offsetting current variation of the gate quiescent current of the GaN power amplifier due to temperature variation, so as to keep the gate quiescent current constant.

As a preferred technical scheme, the temperature compensation circuit comprises a diode and a first resistor which are connected in series in sequence, the diode is grounded, and the first resistor is connected with the output end of the controller.

As a preferable technical solution, the power supply further comprises a second filter circuit, wherein the second filter circuit is connected between the negative power supply circuit and the normally closed input port of the negative voltage switch circuit, and is used for filtering the negative voltage output by the negative power supply circuit.

As a preferable technical solution, the device further comprises an overshoot cancellation circuit, connected between the output port of the negative voltage switch circuit and the gate of the GaN power amplifier, for canceling an overshoot interference signal and a ringing signal in the negative voltage output by the negative voltage switch circuit.

As a preferable technical solution, the power amplifier further comprises a third filter circuit, wherein the third filter circuit is connected between the overshoot elimination circuit and the gate of the GaN power amplifier, and is used for filtering the negative voltage output by the overshoot elimination circuit.

Preferably, an output port of the negative voltage switch circuit is connected to the negative power supply circuit through a second resistor.

As a preferred technical solution, the GaN power amplifier further includes a drain power switch circuit connected to the controller and the drain of the GaN power amplifier, wherein the controller is configured to output a drain power switch signal to the drain power switch circuit, and the drain power switch circuit is configured to receive the drain switch signal output by the controller to implement switching control when the drain of the GaN power amplifier is powered.

According to the GaN power amplifier, the negative voltage switch circuit is arranged, so that the negative grid voltage of the GaN power amplifier can be controlled to be rapidly switched between the negative voltage output by the negative power supply circuit and the negative voltage output by the controller (namely the normal working voltage of the grid electrode of the GaN power amplifier), the GaN power amplifier can be controlled to be rapidly switched between closing and opening, and the GaN power amplifier is simple in structure, reliable in performance and low in cost.

[ description of the drawings ]

To further disclose the specific technical content of the present disclosure, please refer to the attached drawings, wherein:

fig. 1 is a schematic block diagram of a power amplifier grid voltage switching device according to an embodiment of the present invention;

fig. 2 is a schematic circuit diagram of the power amplifier gate voltage switching device shown in fig. 1.

Description of the symbols:

MCU10 controller 20

Negative power supply circuit 30 drain power switch circuit 40

Negative voltage switch circuit 60 of GaN power amplifier 50

First filter circuit 70 temperature compensation circuit 80

Overshoot cancellation circuit 90 second filter circuit 100

Third filter circuit 110

[ detailed description ] embodiments

Referring to fig. 1 and fig. 2, the present embodiment provides a power amplifier grid voltage switching device, which is applied to a TDD system with time division duplex. The power amplifier grid voltage switching device comprises an MCU10, a controller 20, a negative power circuit 30, a drain power switch circuit 40, a GaN power amplifier 50 and a negative voltage switch circuit 60.

An MCU (micro controller Unit) 10 is connected to the controller 20 through a bus, and is used to initialize and set up, and control the operation of the controller 20. The MCU10 is not shown in fig. 2.

The controller 20 is an ADC (analog-to-digital conversion)/DAC (digital-to-analog conversion) controller. The controller 20 is used to output a negative voltage, for example, -5V (volts), which is output via an output terminal of the controller 20. The negative voltage output by the controller 20 is the normal operating voltage of the gate of the GaN power amplifier 50, i.e., the negative gate voltage. In practical applications, the negative voltage output by the controller 20 may be adjusted according to the normal operating voltage of the gate of the GaN power amplifier 50.

The negative power supply circuit 30 is connected to a negative power supply of the controller 20 and a negative power supply Vee port of the negative voltage switch circuit 60, and is configured to supply power to the negative power supply of the controller 20 and the negative voltage switch circuit 60. The negative power supply circuit 30 is preferably a Vss supply, typically a-5V supply.

The drain power switch circuit 40 is a Vpp drain power switch circuit. The drain power switch circuit 40 is respectively connected to the controller 20 and the drain of the GaN power amplifier 50, the controller 20 is configured to output a drain power switch signal to the drain power switch circuit 40, and the drain power switch circuit 40 is configured to receive the drain switch signal output by the controller 20 to implement switching control when the drain of the GaN power amplifier 50 is powered. The drain power switching circuit 40 is not shown in fig. 2.

In practical applications, when the device is powered on, the controller 20 has two states: when the controller 20 is not initialized and the parameters are not matched, it controls the signal of the drain power switch circuit 40 to be high level (protection state), and the drain power switch circuit 40 is turned off, so that the Vpp drain power does not supply power to the drain of the GaN power amplifier 50, thereby protecting the GaN power amplifier 50 from damage. When the MCU10 controls the controller 20 to complete power-on initialization and configuration of parameters through the bus, and the negative voltage (the negative voltage is the normal operating voltage of the gate of the GaN power amplifier 50) is outputted normally, the controller 20 controls the signal of the drain power switch circuit 40 to be at a low level (normal state), the drain power switch circuit 40 is turned on, so that the Vpp drain power supplies power to the drain of the GaN power amplifier 50, and the GaN power amplifier 50 is normally powered on.

The Select control pin of the negative voltage switch circuit 60 is used to receive the TDD switching signal. The ground port GND of the negative voltage switch circuit 60 is used for ground. The normally open input port B1 of the negative voltage switch circuit 60 is connected to the output terminal of the controller 20, the normally closed input port B0 of the negative voltage switch circuit 60 is connected to the negative power supply circuit 30, and the output port a of the negative voltage switch circuit 60 is connected to the negative power supply circuit 30 and the gate of the GaN power amplifier 50, respectively.

The negative voltage switch circuit 60 is configured to turn on the normally closed input port B0 and the output port a to apply a negative voltage output from the negative power supply circuit 30, i.e., -5V, to the gate of the GaN power amplifier 50 when the TDD switch signal is at a low level, thereby turning off the GaN power amplifier 50, and turn on the normally open input port B1 and the output port a to apply the negative voltage output from the controller 20, i.e., a negative gate voltage when the gate of the GaN power amplifier 50 is operating normally, to the gate of the GaN power amplifier 50 when the TDD switch signal is at a high level, thereby turning on the GaN power amplifier 50.

Through the structure, the negative voltage switch circuit 60 can control the negative grid voltage of the GaN power amplifier 50 to be rapidly switched between the negative voltage output by the negative power supply circuit 30 and the negative voltage output by the controller 20 (namely the normal working voltage of the grid electrode of the GaN power amplifier 50), so that the GaN power amplifier 50 is controlled to be rapidly switched between closing and opening, and the GaN power amplifier is simple in structure, reliable in performance and low in cost. Since the device of the present invention is independent of the drain voltage of the GaN power amplifier 50, the device of the present invention does not have to turn off the drain voltage of the GaN power amplifier 50 during the switching operation.

Preferably, the negative voltage switch circuit 60 is preferably a negative voltage SPDT (Single Pole Double Throw) Single Pole Double Throw electronic switch.

Further, the apparatus further includes a first filter circuit 70, a temperature compensation circuit 80, an overshoot elimination circuit 90, a second filter circuit 100, and a third filter circuit 110.

The first filter circuit 70 is connected between the output terminal of the controller 20 and the normally open input port B1 of the negative voltage switch circuit 60, and is used for filtering the negative voltage output by the controller 20 to filter the stray interference of the negative voltage output by the controller 20, so as to obtain a pure negative voltage.

The first filter circuit 70 includes a first capacitor C1 and a second capacitor C2 connected in parallel between the output terminal of the controller 20 and the normally-open input port B1 of the negative voltage switch circuit 60, and the first capacitor C1 and the second capacitor C2 are respectively connected to ground.

The temperature compensation circuit 80 is connected to the output end of the controller 20, and is used for offsetting current variation caused by temperature variation of the gate quiescent current of the GaN power amplifier 50, so that the gate quiescent current is kept constant, and the stability of the circuit operating parameters is ensured.

The temperature compensation circuit 80 includes a diode D1 and a first resistor R1 connected in series, the diode D1 is grounded, and the first resistor R1 is connected to the output terminal of the controller 20. By utilizing the negative temperature coefficient characteristic of the diode D1, the grid quiescent current change caused by the temperature change is counteracted to a certain extent, and the stability of the circuit working parameters is ensured.

The second filter circuit 100 is connected between the negative power supply circuit 30 and the normally closed input port B0 of the negative voltage switch circuit 60, and is configured to filter the negative voltage output by the negative power supply circuit 30, so as to filter the spurious interference signal of the negative voltage output by the negative power supply circuit 30, thereby obtaining a pure negative voltage. The second filter circuit 100 is not shown in fig. 1.

The second filter circuit 100 includes a third capacitor C3 and a fourth capacitor C4 connected in parallel between the negative power circuit 30 and the normally closed input port B0 of the negative voltage switch circuit 60, and the third capacitor C3 and the fourth capacitors C4 are respectively connected to ground.

The overshoot cancellation circuit 90 is connected between the output port a of the negative voltage switch circuit 60 and the gate of the GaN power amplifier 50, and is configured to cancel the overshoot interference signal and the ringing signal in the negative voltage output by the negative voltage switch circuit 60 to obtain a pure square wave signal.

The overshoot cancellation circuit 90 includes an inductor L1, a fifth capacitor C5, and a sixth capacitor C6. The inductor L1 is connected in series between the output port a of the negative voltage switch circuit 60 and the gate of the GaN power amplifier 50. The fifth capacitor C5 is connected in parallel between the output port a of the negative voltage switch circuit 60 and the inductor L1 and is grounded. The sixth capacitor C6 is connected in parallel between the inductor L1 and the gate of the GaN power amplifier 50 and to ground.

The third filter circuit 110 is connected between the overshoot cancellation circuit 90 and the gate of the GaN power amplifier 50, and is configured to filter the negative voltage output by the overshoot cancellation circuit 90, so as to filter the spurious interference signal in the negative voltage output by the overshoot cancellation circuit 90, thereby obtaining a pure square wave signal. The third filter circuit 110 has a similar structure to the first filter circuit 70 and the second filter circuit 100, and filters the negative voltage output by the overshoot cancellation circuit 90 through two capacitors. The third filter circuit 110 is not shown in fig. 2.

Further, the output port a of the negative voltage switch circuit 60 is connected to the negative power supply circuit 30 through a second resistor R2. When the Select control pin of the negative voltage switch circuit 60 is switched between high and low levels, the gate of the GaN power amplifier 50 may be in a floating state at the switching moments of the normally closed input port B0 and the normally open input port B1 at the output port a of the negative voltage switch circuit 60, and there is no negative voltage, which is not allowed. Therefore, the output port a of the negative voltage switch circuit 60 is connected to the negative power circuit 30(-5V) via the second resistor R2, which makes the voltage of the output port a always maintain at the-5V power state during the switching process of the negative voltage switch circuit 60, and makes the channel of the GaN power amplifier 50 always maintain at the clamped state during the switching process, so as to ensure that the GaN power amplifier 50 is not damaged.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.