Switch driving circuit

Abstract

The utility model discloses a switch driving circuit, which can replace a switch driving chip to provide driving voltage for a switch circuit, is low in manufacturing cost, and can solve the problem of high cost when the switch driving chip is used. In addition, the switch driving circuit can also output a backward voltage with a higher voltage value. Comprising a first PNP type triode switching circuit, a diode switching circuit and a second PNP type triode switching circuit, when a low-level control signal is input into the signal input end of the driving circuit, the first PNP type triode and the diode are conducted, the second PNP type triode is cut off, and the signal output end of the driving circuit outputs forward voltage from a positive power supply of the driving circuit; when a high-level control signal is input into the signal input end of the driving circuit, the first PNP type triode and the diode are cut off, the second PNP type triode is switched on, and the signal output end of the driving circuit outputs reverse voltage from the negative power supply of the driving circuit.

Description

Technical Field

[0001] The utility model relates to a switch driving circuit, which is used for providing a driving voltage for a switch circuit, in particular for providing a driving voltage for a high-power switch of a microwave device. Background Art

[0002] At present, the high-power switch of microwave equipment is usually driven by a switch driver chip. This switch driver chip is expensive, resulting in high cost of use. In addition, this high-power switch requires a larger reverse bias voltage, while the reverse voltage output by the general switch driver chip can only reach about -50V, which is difficult to meet the use requirements of high-power microwave switches. Utility Model Content

[0003] The purpose of the utility model is to provide a switch driving circuit, which can replace the switch driving chip to provide a driving voltage for the switch circuit, and the manufacturing cost of the switch driving circuit is low, which can solve the problem of high cost of using the switch driving chip. In addition, the switch driving circuit can also output a reverse voltage with a higher voltage value.

[0004] A switch drive circuit, comprising: a first PNP-type triode switch circuit, the first PNP-type triode switch circuit comprises a first PNP-type triode, the base of the first PNP-type triode is connected to a drive circuit signal input terminal, the emitter of the first PNP-type triode is connected to a drive circuit positive power supply, the drive circuit signal input terminal is used to input one of a low-level control signal and a high-level control signal; a diode switch circuit, the diode switch circuit comprises a diode, the input terminal of the diode is connected to the collector of the first PNP-type triode, the output terminal of the diode is connected to the drive circuit signal output terminal; a second PNP-type triode switch circuit, the second PNP-type triode switch circuit comprises a second PNP-type triode, the first The base of the second PNP transistor is connected to the input end of the diode at the same potential, the emitter of the second PNP transistor is connected to the output end of the diode at the same potential, and the collector of the second PNP transistor is connected to the negative power supply of the drive circuit; when a low-level control signal is input to the signal input end of the drive circuit, the first PNP transistor and the diode are turned on and the second PNP transistor is turned off, and the signal output end of the drive circuit outputs a forward voltage from the positive power supply of the drive circuit; when a high-level control signal is input to the signal input end of the drive circuit, the first PNP transistor and the diode are turned off and the second PNP transistor is turned on, and the signal output end of the drive circuit outputs a reverse voltage from the negative power supply of the drive circuit.

[0005] The switch drive circuit is mainly constructed by combining traditional devices such as triodes and diodes, which has low manufacturing cost and can significantly reduce the cost of use. Devices with voltage resistance requirements can be selected according to needs, so that a higher reverse voltage can be output.

[0006] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Additional aspects and advantages provided by the present invention will be partially given in the following description, partially become apparent from the following description, or be understood through practice. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The drawings constituting a part of this specification are used to assist the understanding of the present invention. The contents provided in the drawings and their related descriptions in the present invention are used to explain the present invention, but do not constitute improper limitations on the present invention.

[0008] Figure 1 The figure is a schematic diagram of the structure of a switch driving circuit according to an embodiment of the utility model. DETAILED DESCRIPTION

[0009] The utility model is described clearly and completely below in conjunction with the accompanying drawings. A person skilled in the art will be able to implement the utility model based on these descriptions. Before describing the utility model in conjunction with the accompanying drawings, it should be particularly noted that:

[0010] The technical solutions and technical features provided in each section, including the following description, can be combined with each other without conflict. In addition, where possible, these technical solutions, technical features and related combinations can be assigned specific technical themes and protected by relevant patents.

[0011] The embodiments of the utility model involved in the following description are usually only a part of the embodiments rather than all the embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of patent protection.

[0012] The terms "include", "comprises" and any variations thereof in this utility model and the corresponding claims and related parts are intended to cover non-exclusive inclusions. Other related terms and units can be reasonably interpreted based on the relevant content provided in this utility model.

[0013] Figure 1 FIG. 1 is a schematic diagram of a switch driving circuit according to an embodiment of the present utility model. Figure 1 As shown, a switch driving circuit is used to provide a driving voltage for a high-power switch of a microwave device, comprising:

[0014] A first PNP transistor switch circuit, the first PNP transistor switch circuit comprising a first PNP transistor Q1, the base of the first PNP transistor Q1 is connected to a drive circuit signal input terminal IN1, the emitter of the first PNP transistor Q1 is connected to a drive circuit positive power supply VCC, and the drive circuit signal input terminal IN1 is used to input one of a low-level control signal and a high-level control signal;

[0015] A diode switch circuit, wherein the diode switch circuit comprises a diode D1, wherein an input end of the diode D1 is connected to the collector of the first PNP transistor Q1, and an output end of the diode D1 is connected to a signal output end OUT1 of a driving circuit;

[0016] A second PNP transistor switch circuit, the second PNP transistor switch circuit comprises a second PNP transistor Q2, the base of the second PNP transistor Q2 is connected to the input end of the diode D1 at the same potential, the emitter of the second PNP transistor Q2 is connected to the output end of the diode D1 at the same potential, and the collector of the second PNP transistor Q2 is connected to the negative power supply VEE of the driving circuit;

[0017] When a low-level control signal is input to the drive circuit signal input terminal IN1, the first PNP transistor Q1 and the diode D1 are turned on and the second PNP transistor Q2 is turned off, and the drive circuit signal output terminal OUT1 outputs a forward voltage from the drive circuit positive power supply VCC;

[0018] When a high level control signal is input to the drive circuit signal input terminal IN1, the first PNP transistor Q1 and the diode D1 are turned off and the second PNP transistor Q2 is turned on, and the drive circuit signal output terminal OUT1 outputs a reverse voltage from the drive circuit negative power supply VEE.

[0019] Specifically, the signal input terminal IN1 of the driving circuit is connected to the base of the first PNP transistor Q1 via a first resistor R1, and the positive power supply VCC of the driving circuit is connected to the base of the first PNP transistor Q1 via a second resistor R2; and:

[0020] When a low-level control signal is input to the drive circuit signal input terminal IN1, the voltage value of the low-level control signal is lower than the voltage value of the drive circuit positive power supply VCC. At this time, the second resistor R2 and the first resistor R1 are arranged in a front-to-back direction from the drive circuit positive power supply VCC to the drive circuit signal input terminal IN1 to form a voltage divider circuit located between the drive circuit positive power supply VCC and the drive circuit signal input terminal IN1.

[0021] When a high-level control signal is input to the signal input terminal IN1 of the driving circuit, the voltage value of the high-level control signal is ≥ the voltage value of the positive power supply VCC of the driving circuit.

[0022] In addition, a first capacitor C1 connected in parallel with the first resistor R1 may be disposed between the signal input terminal IN1 of the driving circuit and the base of the first PNP transistor Q1 .

[0023] By using the voltage divider circuit, the base voltage of the first PNP transistor Q1 is lower than the emitter voltage of the first PNP transistor Q1, and the first PNP transistor Q1 is further turned on.

[0024] The first resistor R1 can play a current limiting role to prevent the base current of the first PNP transistor Q1 from being too large and thus damaging the first PNP transistor Q1.

[0025] The combination of the first resistor R1 and the first capacitor C1 can improve the transient response of the switch driving circuit to the input signal of the circuit signal input terminal IN1 and suppress high-frequency noise.

[0026] In addition, the emitter of the first PNP transistor Q1 can also be connected to a second capacitor C2, one end of the second capacitor C2 is connected to the positive power supply VCC of the driving circuit and has an equipotential, and the other end of the second capacitor C2 is grounded.

[0027] The second capacitor C2 is connected between the positive power supply VCC of the driving circuit and the ground, and can provide a local low-impedance power supply for the first PNP type transistor Q1. When the driving circuit signal input terminal IN1 switches the state, the base of the first PNP type transistor Q1 will change instantaneously, which may cause instantaneous interference on the positive power supply VCC of the driving circuit, and the second capacitor C2 can filter out high-frequency noise to ensure that the working environment of the first PNP type transistor Q1 is stable. In addition, the second capacitor C2 can also suppress noise interference from other circuit parts to prevent them from being coupled to the first PNP type transistor Q1 through the positive power supply VCC of the driving circuit. In addition, the second capacitor C2 also has the function of energy storage and increasing the switching speed.

[0028] In addition, the collector of the first PNP transistor Q1 can also be connected to the input end of the diode D1 through the third resistor R3. Here, the third resistor R3 mainly functions to limit the current. When the first PNP transistor Q1 is turned on, the third resistor R3 limits the collector current of the first PNP transistor Q1 from being too large and damaging the first PNP transistor Q1.

[0029] In addition, the negative power supply VEE of the driving circuit and the base of the second PNP transistor Q2 can also be connected via a fourth resistor R4. The fourth resistor R4 is mainly used for voltage division.

[0030] The absolute value of the voltage of the negative power supply VEE of the driving circuit may be ≥50V. For example, the absolute value of the voltage of the negative power supply VEE of the driving circuit may be ≥100V.

[0031] In this embodiment, the voltage value of the positive power supply VCC of the driving circuit is +5V, the voltage value of the low level control signal is 0V, the voltage value of the high level control signal is +5V, and the voltage value of the negative power supply VEE of the driving circuit is -100V.

[0032] In this embodiment, the resistance value of the first resistor R1 is 1000 ohms, the resistance value of the second resistor R2 is 560 ohms, the resistance value of the third resistor R3 is 680 ohms, and the resistance value of the fourth resistor R4 is 68 kilo-ohms.

[0033] Therefore, when a low-level control signal (0V) is input to the signal input terminal IN1 of the driving circuit, the first PNP transistor Q1 is turned on, the diode D1 is turned on, and the signal output terminal OUT1 of the driving circuit outputs a forward voltage; when a high-level control signal (+5V) is input to the signal input terminal IN1 of the driving circuit, the first PNP transistor Q1 is turned off, the diode D1 is turned off, the second PNP transistor Q2 is turned on, and the signal output terminal OUT1 of the driving circuit outputs a reverse voltage VEE.

[0034] The above is a description of the relevant contents of the utility model. A person skilled in the art will be able to implement the utility model based on these descriptions. Based on the above contents of this specification, all other embodiments obtained by a person skilled in the art without making any creative work shall fall within the scope of the utility model.

Claims

1. A switch driving circuit, characterized in that: include: A first PNP transistor switch circuit, the first PNP transistor switch circuit comprising a first PNP transistor (Q1), a base of the first PNP transistor (Q1) connected to a drive circuit signal input terminal (IN1), an emitter of the first PNP transistor (Q1) connected to a drive circuit positive power supply (VCC), and the drive circuit signal input terminal (IN1) is used to input one of a low-level control signal and a high-level control signal; A diode switch circuit, the diode switch circuit comprising a diode (D1), an input end of the diode (D1) being connected to the collector of the first PNP-type transistor (Q1), and an output end of the diode (D1) being connected to a signal output end (OUT1) of a drive circuit; a second PNP transistor switch circuit, the second PNP transistor switch circuit comprising a second PNP transistor (Q2), the base of the second PNP transistor (Q2) being connected to the input end of the diode (D1) at the same potential, the emitter of the second PNP transistor (Q2) being connected to the output end of the diode (D1) at the same potential, and the collector of the second PNP transistor (Q2) being connected to a negative power supply (VEE) of a driving circuit; When a low-level control signal is input to the drive circuit signal input terminal (IN1), the first PNP transistor (Q1) and the diode (D1) are turned on and the second PNP transistor (Q2) is turned off, and the drive circuit signal output terminal (OUT1) outputs a forward voltage from the drive circuit positive power supply (VCC); When a high-level control signal is input to the signal input terminal (IN1) of the drive circuit, the first PNP transistor (Q1) and the diode (D1) are turned off and the second PNP transistor (Q2) is turned on, and the signal output terminal (OUT1) of the drive circuit outputs a reverse voltage from a negative power supply (VEE) of the drive circuit.

2. A switch driving circuit as claimed in claim 1, characterized in that: The signal input terminal (IN1) of the driving circuit is connected to the base of the first PNP transistor (Q1) via a first resistor (R1), and the positive power supply (VCC) of the driving circuit is connected to the base of the first PNP transistor (Q1) via a second resistor (R2); When a low-level control signal is input to the drive circuit signal input terminal (IN1), the voltage value of the low-level control signal is lower than the voltage value of the drive circuit positive power supply (VCC). At this time, the second resistor (R2) and the first resistor (R1) are arranged in a front-to-back direction from the drive circuit positive power supply (VCC) to the drive circuit signal input terminal (IN1) to form a voltage divider circuit located between the drive circuit positive power supply (VCC) and the drive circuit signal input terminal (IN1); When a high-level control signal is input to the signal input terminal (IN1) of the driving circuit, the voltage value of the high-level control signal is ≥ the voltage value of the positive power supply (VCC) of the driving circuit.

3. A switch driving circuit as claimed in claim 2, characterized in that: A first capacitor (C1) connected in parallel with the first resistor (R1) is also provided between the signal input terminal (IN1) of the driving circuit and the base of the first PNP transistor (Q1).

4. A switch driving circuit as claimed in claim 1, characterized in that: The emitter of the first PNP transistor (Q1) is also connected to a second capacitor (C2), one end of the second capacitor (C2) is connected to the positive power supply (VCC) of the driving circuit at the same potential, and the other end of the second capacitor (C2) is grounded.

5. A switch driving circuit as claimed in claim 1, characterized in that: The collector of the first PNP transistor (Q1) is connected to the input end of the diode (D1) via a third resistor (R3).

6. A switch driving circuit as claimed in claim 1, characterized in that: The negative power supply (VEE) of the driving circuit is connected to the base of the second PNP transistor (Q2) via a fourth resistor (R4).

7. A switch driving circuit according to claim 1, characterized in that: The absolute value of the voltage of the negative power supply (VEE) of the driving circuit is ≥50V.

8. A switch driving circuit as claimed in claim 7, characterized in that: The absolute value of the voltage of the negative power supply (VEE) of the driving circuit is ≥100V.

9. A switch driving circuit as claimed in claim 1, characterized in that: The signal input terminal (IN1) of the driving circuit and the base of the first PNP transistor (Q1) are connected via a first resistor (R1), and the positive power supply (VCC) of the driving circuit and the base of the first PNP transistor (Q1) are connected via a second resistor (R2); When a low-level control signal is input to the drive circuit signal input terminal (IN1), the voltage value of the low-level control signal is lower than the voltage value of the drive circuit positive power supply (VCC), at this time, the second resistor (R2) and the first resistor (R1) are arranged in a front-to-back direction from the drive circuit positive power supply (VCC) to the drive circuit signal input terminal (IN1) to form a voltage divider circuit located between the drive circuit positive power supply (VCC) and the drive circuit signal input terminal (IN1); When a high-level control signal is input to the signal input terminal (IN1) of the driving circuit, the voltage value of the high-level control signal is ≥ the voltage value of the positive power supply (VCC) of the driving circuit; The collector of the first PNP transistor (Q1) is connected to the input end of the diode (D1) via a third resistor (R3); The negative power supply (VEE) of the driving circuit is connected to the base of the second PNP transistor (Q2) via a fourth resistor (R4); Among them, the voltage value of the positive power supply (VCC) of the driving circuit is +5V, the voltage value of the low-level control signal is 0V, the voltage value of the high-level control signal is +5V, and the voltage value of the negative power supply (VEE) of the driving circuit is -100V.

10. A switch driving circuit as claimed in claim 9, characterized in that: The resistance value of the first resistor (R1) is 1000 ohms, the resistance value of the second resistor (R2) is 560 ohms, the resistance value of the third resistor (R3) is 680 ohms, and the resistance value of the fourth resistor (R4) is 68 kilo ohms.

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