CN214704379U

CN214704379U - Radio frequency electronic switch based on single chip microcomputer control

Info

Publication number: CN214704379U
Application number: CN202121214452.1U
Authority: CN
Inventors: 苟海军
Original assignee: Chengdu Daqiying Technology Co ltd
Current assignee: Chengdu Daqiying Technology Co ltd
Priority date: 2021-06-01
Filing date: 2021-06-01
Publication date: 2021-11-12
Anticipated expiration: 2031-06-01

Abstract

The utility model provides a radio frequency electronic switch based on single chip microcomputer control, wherein, a drive circuit of a radio frequency change-over switch comprises a control port connected with a single chip microcomputer; the first RC filter circuit is connected with the control port; a first inverter connected to the first RC filter circuit; a second inverter connected to the first inverter; a driver connected to the second inverter; a first control pin of the driver is connected with the output end of the second inverter; a second control pin of the driver is connected with the input end of the second inverter; a first shunt pin of the driver is connected with a first bias voltage pin of the radio frequency switch through a first resistor; a second shunt pin of the driver is connected with a second bias voltage pin of the radio frequency selector switch through a second resistor; a first series pin of the driver is connected with a first output pin of the radio frequency switch; and a second series pin of the driver is connected with a second output pin of the radio frequency switch.

Description

Radio frequency electronic switch based on single chip microcomputer control

Technical Field

The utility model relates to a radio frequency communication technical field particularly, relates to a radio frequency electronic switch based on single chip microcomputer control.

Background

At present, with the development of radio technology, the application range of radio frequency switches is wider and wider, the requirements on the performance of the switches such as size, adaptive frequency, power, isolation, insertion loss and the like are higher and higher, especially when a plurality of switches are cascaded or used simultaneously, the influence of signals between the switches needs to be reduced, and high-isolation switches are more and more important for the radio frequency switches. Secondly, the electronic rf switch has the advantages of small size, light weight, fast switching speed, long service life, etc. compared with the mechanical switch, and is becoming the first choice of the rf switch. However, the isolation of the current rf electronic switch is poor, and the noise figure is large, so a solution is needed to provide the isolation of the rf electronic switch and reduce the noise figure at the same time.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a radio frequency electronic switch based on single chip microcomputer control for realize reducing noise figure's technological effect when improving radio frequency electronic switch's isolation.

The embodiment of the utility model provides a radio frequency electronic switch based on single chip microcomputer control, which comprises a level conversion circuit; the singlechip is connected with the level conversion circuit; the driving circuit is connected with the single chip microcomputer; the radio frequency switch is connected with the driving circuit; the radio frequency input circuit is connected with the radio frequency selector switch; the first radio frequency output interface and the second radio frequency output interface are connected with the radio frequency selector switch; the driving circuit comprises a control port connected with the single chip microcomputer; the first RC filter circuit is connected with the control port; a first inverter connected to the first RC filter circuit; a second inverter connected to the first inverter; a driver connected to the second inverter; a first control pin of the driver is connected with the output end of the second inverter; a second control pin of the driver is connected with the input end of the second inverter; a first shunt pin of the driver is connected with a first bias voltage pin of the radio frequency switch through a first resistor; a second shunt pin of the driver is connected with a second bias voltage pin of the radio frequency switch through a second resistor; a first series pin of the driver is connected with a first output pin of the radio frequency selector switch; and a second series pin of the driver is connected with a second output pin of the radio frequency change-over switch.

Further, the radio frequency electronic switch further comprises: the second RC filter circuit is arranged between the first shunt pin of the driver and the first resistor, and the third RC filter circuit is arranged between the second shunt pin of the driver and the second resistor.

Further, the second RC filter circuit comprises a third resistor, a fourth resistor and a first capacitor; a first end of the first resistor is connected with a first shunt pin of the driver; the first end of the fourth resistor is connected with the second end of the third resistor; the first end of the first capacitor and the first end of the first resistor are both connected with the second end of the fourth resistor; the third RC filter circuit comprises a fifth resistor, a sixth resistor and a second capacitor; a first end of the fifth resistor is connected with a second shunt pin of the driver; the first end of the sixth resistor is connected with the second end of the fifth resistor; the first end of the second capacitor and the first end of the second resistor are both connected with the second end of the sixth resistor; the second end of the first capacitor and the second end of the second capacitor are both grounded.

Furthermore, the current on the circuit where the first resistor, the third resistor and the fourth resistor are located should be not lower than 10mA, and the resistance value of the first resistor should be much smaller than the sum of the resistance value of the third resistor and the resistance value of the fourth resistor; the current on the circuit where the second resistor, the fifth resistor and the sixth resistor are located is not lower than 10mA, and the resistance value of the second resistor is far smaller than the sum of the resistance value of the fifth resistor and the resistance value of the sixth resistor.

Further, the radio frequency electronic switch further comprises: the first LC filter circuit is arranged between a first series pin of the driver and a first output end of the radio frequency switch; and the second LC filter circuit is arranged between the second series pin of the driver and the second output end of the radio frequency switch.

Further, the first LC filter circuit includes a first inductor and a first ground capacitor; the second LC filter circuit comprises a second inductor and a second grounding capacitor; the first grounding capacitor and the first end of the first inductor are both connected with a first series pin of the driver; the second end of the first inductor is connected with the first output end of the radio frequency switch; the second grounding capacitor and the first end of the second inductor are both connected with a second series pin of the driver; a second end of the second inductor is connected with a second output end of the radio frequency switch; and the first inductor and the second inductor are both in I-shaped structures formed by connecting three inductance coils end to end.

Further, the radio frequency electronic switch further comprises a power supply module; the power supply module comprises a power supply interface and a DC/DC converter connected with the power supply interface; the DC/DC converter is respectively connected with the single chip microcomputer and the driving circuit and used for supplying power to the single chip microcomputer and the driving circuit.

Further, the radio frequency electronic switch further comprises: the fourth RC filter circuit is arranged between the first series pin of the driver and the first output end of the radio frequency switch; and the fifth RC filter circuit is arranged between the second series pin of the driver and the second output end of the radio frequency change-over switch.

Further, the radio frequency input circuit comprises a radio frequency input port, a voltage input port, a third capacitor, a fourth capacitor, a seventh resistor and a third inductor; the first end of the third capacitor is connected with the radio frequency input port; a second end of the fourth capacitor and a first end of the third inductor are both connected with a first control pin of the driver; a first end of the fourth capacitor and a first end of the seventh resistor are both connected with a second end of the third inductor; and the second end of the seventh resistor is connected with the voltage input port.

Further, the radio frequency electronic switch further comprises: the fifth capacitor is arranged between the first radio frequency output interface and the first output end of the radio frequency selector switch; and a sixth capacitor arranged between the second radio frequency output interface and the second output end of the radio frequency change-over switch.

The utility model discloses the beneficial effect that can realize is: the utility model provides a radio frequency electronic switch controls radio frequency change over switch through the singlechip and the drive circuit that set up, has reduced the noise figure in the circuit when improving radio frequency electronic switch's isolation.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to these drawings without inventive efforts.

Fig. 1 is a schematic view of a topology structure of a radio frequency electronic switch according to an embodiment of the present invention;

fig. 2 is a schematic circuit diagram of a driver according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a radio frequency input circuit according to an embodiment of the present invention;

fig. 4 is a schematic circuit diagram of a radio frequency switch according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of an inductor according to an embodiment of the present invention.

Icon: 10-radio frequency electronic switch; 100-level shift circuit; 200-a single chip microcomputer; 300-a drive circuit; 400-a radio frequency switch; 500-a first radio frequency output interface; 600-a second radio frequency output interface; 700-a radio frequency input circuit; 800-power module.

Detailed Description

The technical solution in the embodiment of the present invention will be described below with reference to the accompanying drawings in the embodiment of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present invention, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.

Please refer to fig. 1, fig. 2, fig. 3, fig. 4 and fig. 5, in which fig. 1 is a schematic diagram of a topology structure of a radio frequency electronic switch according to an embodiment of the present invention; fig. 2 is a schematic circuit diagram of a driver according to an embodiment of the present invention; fig. 3 is a schematic diagram of a radio frequency input circuit according to an embodiment of the present invention; fig. 4 is a schematic circuit diagram of a radio frequency switch according to an embodiment of the present invention; fig. 5 is a schematic structural diagram of an inductor according to an embodiment of the present invention.

As shown in fig. 1 and fig. 2, in one embodiment, the embodiment of the present invention provides a radio frequency electronic switch 10 controlled by a single chip microcomputer 200, including a level conversion circuit 100; a single chip microcomputer 200 connected to the level conversion circuit 100; a driving circuit 300 connected to the single chip microcomputer 200; a radio frequency switch 400 connected to the driving circuit 300; a radio frequency input circuit 700 connected to the radio frequency switch 400; a first rf output interface 500 and a second rf output interface 600 connected to the rf switch 400; the driving circuit 300 includes a control port (P4) connected to the single chip microcomputer 200; a first RC filter circuit 310 connected to the control port (P4); a first inverter (U2A) connected to the first RC filter circuit 310; a second inverter (U2B) connected to the first inverter (U2A); a driver (U1) connected to the second inverter (U2B); a first control pin (pin 2) of the driver (U1) is connected with the output end of the second inverter (U2B); a second control pin (pin 11) of the driver (U1) is connected with the input end of the second inverter (U2B); a first shunt pin (SH1) of the driver (U1) is connected with a first bias voltage pin (B4) of the radio frequency switch through a first resistor (R1); a second shunt pin (SH2) of the driver (U1) is connected to a second bias voltage pin (B5) of the rf switch 400 through a second resistor (R2); a first series pin (SER1) of the driver is connected with a first output pin of the radio frequency switch 400; the second series pin (SER2) of the driver is connected to the second output pin of the rf switch 400.

In the implementation process, the level conversion circuit 100 can convert the input control level into a TTL level, and the single chip microcomputer 200 scans the TTL level and performs a control action according to the TTL level; the driving circuit 300 completes switching of the switches according to the received control action; by the first RC filter circuit (circuit composed of R9 and C12), the first inverter (U2A), the second inverter (U2B), and the like provided in the drive circuit 300, the switching noise floor can be improved while the radio frequency switch 400 is controlled, thereby reducing the noise figure.

For example, the first inverter (U2A) and the second inverter (U2B) may use a chip with a double inverter, and the driver (U1) may have a model of MADR-010574; the rf switch 400 may be a single-pole double-throw type switch (e.g., a type MASW-011055 rf switch). The specific control logic is shown in table 1. When the single chip microcomputer 200 gives a high level, a pin (SER1) of the driver (U1) outputs a low level, a pin (SER2) outputs a high level, and at the moment, the RFC- > RF1 of the radio frequency switch 400 is switched on, and the RFC- > RF2 is switched off; when the single chip microcomputer 200 outputs a low level, the pin (SER1) of the driver (U1) outputs a high level, the pin (SER2) outputs a low level, and at the moment, the RFC- > RF2 of the radio frequency switch 400 is turned on, and the RFC- > RF1 is turned off. Through the above process, the control of the radio frequency changeover switch 400 is realized.

TABLE 1 control logic table

Serial number

Control level

SH1

SER1

SH2

SER2

Connecting channel

1

5V

120V

0

120V

P1->P2

2

0

120V

0

P1->P3

In one embodiment, the radio frequency electronic switch 10 further comprises: the circuit comprises a second RC filter circuit arranged between a first shunt pin (SH1) of a driver (U1) and a first resistor (R1), and a third RC filter circuit arranged between the second shunt pin of the driver and a second resistor (R2).

Illustratively, the second RC filter circuit includes a third resistor (R3), a fourth resistor (R4), and a first capacitor (C1); a first end of the first resistor (R1) is connected with a first shunt pin (SH1) of the driver (U1); a first terminal of the fourth resistor (R4) is connected to a second terminal of the third resistor (R3); a first end of the first capacitor (C1) and a first end of the first resistor (R1) are both connected with a second end of the fourth resistor (R4); the third RC filter circuit comprises a fifth resistor (R5), a sixth resistor (R6) and a second capacitor (C2); a first end of the fifth resistor (R5) is connected with a second shunt pin of the driver (U1); a first end of the sixth resistor (R6) is connected with a second end of the fifth resistor (R5); a first end of the second capacitor (C2) and a first end of the second resistor (R2) are both connected with a second end of the sixth resistor (R6); the second terminal of the first capacitor (C1) and the second terminal of the second capacitor (C2) are both grounded.

Specifically, the current on the circuit where the first resistor (R1), the third resistor (R3) and the fourth resistor (R4) are located should not be lower than 10mA, and the resistance value of the first resistor (R1) should be much smaller than the sum of the resistance value of the third resistor (R3) and the resistance value of the fourth resistor (R4); the current on the circuit where the second resistor (R2), the fifth resistor (R5) and the sixth resistor (R6) are located should also be not lower than 10mA, and the resistance of the second resistor (R2) should be much smaller than the sum of the resistance of the fifth resistor (R5) and the resistance of the sixth resistor (R6). The first resistor (R1) and the second resistor (R2) are resistors within 100 ohms.

By the driving mode, the noise in the circuit is reduced, and the isolation degree of the switch is improved.

In one embodiment, the radio frequency electronic switch 10 further comprises: a first LC filter circuit disposed between a first series pin (SER1) of the driver (U1) and a first output terminal of the radio frequency switch 400; and a second LC filter circuit disposed between a second series pin (SER2) of the driver (U1) and a second output terminal of the rf switch 400.

As shown in fig. 3 and 4, in one embodiment, the first LC filter circuit includes a first inductor (L1) and a first capacitance to ground (C7); the second LC filter circuit comprises a second inductor (L2) and a second ground capacitor (C8); the first grounding capacitor (C7) and the first end of the first inductor (L1) are both connected with the first series pin (SER1) of the driver (U1); a second terminal of the first inductor (L1) is connected to a first output terminal of the rf switch 400; the first ends of the second grounding capacitor (C8) and the second inductor (L2) are connected with a second series pin (SER2) of the driver (U1); a second terminal of the second inductor (L2) is connected to a second output terminal of the rf switch 400; and the first inductor (L1) and the second inductor (L2) are both in an I-shaped structure formed by connecting three equal inductors end to end.

In the implementation process, the first inductor (L1) and the second inductor (L2) both use an I-shaped structure formed by three equal inductors, and input loss is reduced.

It should be noted that, in one embodiment, the radio frequency electronic switch 10 further includes: a fourth RC filter circuit disposed between the first series pin (SER1) of the driver (U1) and the first output terminal of the rf switch 400; and a fifth RC filter circuit disposed between the second series pin (SER2) of the driver (U1) and the second output terminal of the rf switch 400. Through the LC filter circuit or the RC filter circuit, the input can be filtered, so that the signal is more stable.

In one embodiment, the radio frequency electronic switch 10 further includes a power module 800; the power module 800 includes a power interface, a DC/DC converter connected to the power interface; the DC/DC converter is respectively connected to the single chip microcomputer 200 and the driving circuit 300, and is configured to supply power to the single chip microcomputer 200 and the driving circuit 300. The power supply module can supply power for each electronic element in the single chip microcomputer 200 and the driving circuit 300, and the power supply requirement of each electronic element is met.

In one embodiment, the rf input circuit 700 includes an rf input port (P1), a voltage input port (+5V), a third capacitance (C3), a fourth capacitance (C4), a seventh resistance (R7), and a third inductor (L3); a first end of the third capacitor (C3) is connected with the radio frequency input port (P1); a second terminal of the fourth capacitor (C4) and a first terminal of the third inductor (L3) are both connected to a first control pin of the driver (U1); a first end of a fourth capacitor (C4) and a first end of a seventh resistor (R7) are both connected with a second end of the third inductor (L3); a second terminal of the seventh resistor (R7) is connected to the voltage input port (+ 5V).

Through the circuit, a forward bias conducting voltage can be provided for the radio frequency switch 400, and meanwhile, a direct current signal in a radio frequency signal input by the radio frequency input port is isolated.

In one embodiment, the radio frequency electronic switch 10 further comprises: a fifth capacitor (C5) disposed between the first rf output interface 500 and the first output terminal of the rf switch 400; and a sixth capacitor (C6) disposed between the second rf output interface 600 and the second output terminal of the rf switch 400.

Through the embodiment, the direct current signals in the radio frequency signals output by the radio frequency output interfaces can be further isolated, and the isolation of the signals is further improved.

To sum up, the embodiment of the present invention provides a radio frequency electronic switch based on single chip microcomputer control, which includes a level converting circuit; the singlechip is connected with the level conversion circuit; the driving circuit is connected with the single chip microcomputer; the radio frequency switch is connected with the driving circuit; the radio frequency input circuit is connected with the radio frequency selector switch; the first radio frequency output interface and the second radio frequency output interface are connected with the radio frequency selector switch; the driving circuit comprises a control port connected with the single chip microcomputer; the first RC filter circuit is connected with the control port; a first inverter connected to the first RC filter circuit; a second inverter connected to the first inverter; a driver connected to the second inverter; a first control pin of the driver is connected with the output end of the second inverter; a second control pin of the driver is connected with the input end of the second inverter; a first shunt pin of the driver is connected with a first bias voltage pin of the radio frequency switch through a first resistor; a second shunt pin of the driver is connected with a second bias voltage pin of the radio frequency switch through a second resistor; a first series pin of the driver is connected with a first output pin of the radio frequency selector switch; and a second series pin of the driver is connected with a second output pin of the radio frequency change-over switch.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A radio frequency electronic switch based on single chip microcomputer control, comprising: a level conversion circuit; the singlechip is connected with the level conversion circuit; the driving circuit is connected with the single chip microcomputer; the radio frequency switch is connected with the driving circuit; the radio frequency input circuit is connected with the radio frequency selector switch; the first radio frequency output interface and the second radio frequency output interface are connected with the radio frequency selector switch; the driving circuit comprises a control port connected with the single chip microcomputer; the first RC filter circuit is connected with the control port; a first inverter connected to the first RC filter circuit; a second inverter connected to the first inverter; a driver connected to the second inverter; a first control pin of the driver is connected with the output end of the second inverter; a second control pin of the driver is connected with the input end of the second inverter; a first shunt pin of the driver is connected with a first bias voltage pin of the radio frequency switch through a first resistor; a second shunt pin of the driver is connected with a second bias voltage pin of the radio frequency switch through a second resistor; a first series pin of the driver is connected with a first output pin of the radio frequency selector switch; and a second series pin of the driver is connected with a second output pin of the radio frequency change-over switch.

2. The radio frequency electronic switch according to claim 1, further comprising: the second RC filter circuit is arranged between the first shunt pin of the driver and the first resistor, and the third RC filter circuit is arranged between the second shunt pin of the driver and the second resistor.

3. The radio frequency electronic switch of claim 2, wherein the second RC filter circuit comprises a third resistor, a fourth resistor, and a first capacitor; a first end of the first resistor is connected with a first shunt pin of the driver; the first end of the fourth resistor is connected with the second end of the third resistor; the first end of the first capacitor and the first end of the first resistor are both connected with the second end of the fourth resistor; the third RC filter circuit comprises a fifth resistor, a sixth resistor and a second capacitor; a first end of the fifth resistor is connected with a second shunt pin of the driver; the first end of the sixth resistor is connected with the second end of the fifth resistor; the first end of the second capacitor and the first end of the second resistor are both connected with the second end of the sixth resistor; the second end of the first capacitor and the second end of the second capacitor are both grounded.

4. The radio frequency electronic switch according to claim 3, wherein the current on the circuit where the first resistor, the third resistor and the fourth resistor are located should not be lower than 10mA, and the resistance of the first resistor should be much smaller than the sum of the resistance of the third resistor and the resistance of the fourth resistor; the current on the circuit where the second resistor, the fifth resistor and the sixth resistor are located is not lower than 10mA, and the resistance value of the second resistor is far smaller than the sum of the resistance value of the fifth resistor and the resistance value of the sixth resistor.

5. The radio frequency electronic switch according to claim 1, further comprising: the first LC filter circuit is arranged between a first series pin of the driver and a first output end of the radio frequency switch; and the second LC filter circuit is arranged between the second series pin of the driver and the second output end of the radio frequency switch.

6. The radio frequency electronic switch of claim 5, wherein the first LC filter circuit comprises a first inductor and a first ground capacitor; the second LC filter circuit comprises a second inductor and a second grounding capacitor; the first grounding capacitor and the first end of the first inductor are both connected with a first series pin of the driver; the second end of the first inductor is connected with the first output end of the radio frequency switch; the second grounding capacitor and the first end of the second inductor are both connected with a second series pin of the driver; a second end of the second inductor is connected with a second output end of the radio frequency switch; and the first inductor and the second inductor are both in I-shaped structures formed by connecting three inductance coils end to end.

7. The radio frequency electronic switch according to claim 1, further comprising a power supply module; the power supply module comprises a power supply interface and a DC/DC converter connected with the power supply interface; the DC/DC converter is respectively connected with the single chip microcomputer and the driving circuit and used for supplying power to the single chip microcomputer and the driving circuit.

8. The radio frequency electronic switch according to claim 1, further comprising: the fourth RC filter circuit is arranged between the first series pin of the driver and the first output end of the radio frequency switch; and the fifth RC filter circuit is arranged between the second series pin of the driver and the second output end of the radio frequency change-over switch.

9. The radio frequency electronic switch of claim 1, wherein the radio frequency input circuit comprises a radio frequency input port, a voltage input port, a third capacitance, a fourth capacitance, a seventh resistance, and a third inductor; the first end of the third capacitor is connected with the radio frequency input port; a second end of the fourth capacitor and a first end of the third inductor are both connected with a first control pin of the driver; a first end of the fourth capacitor and a first end of the seventh resistor are both connected with a second end of the third inductor; and the second end of the seventh resistor is connected with the voltage input port.

10. The radio frequency electronic switch according to claim 1, further comprising: the fifth capacitor is arranged between the first radio frequency output interface and the first output end of the radio frequency selector switch; and a sixth capacitor arranged between the second radio frequency output interface and the second output end of the radio frequency change-over switch.