Rapid high-voltage driving circuit

Abstract

The utility model relates to the technical field of electronic circuits, in particular to a fast high-voltage driving circuit, which comprises a field-effect tube Q1, a field-effect tube Q2, a field-effect tube Q3 and a pull-down resistor R5. One end of the pull-down resistor R5 is electrically connected with the single-chip microcomputer, the first end of the field effect transistor Q2 and the first end of the field effect transistor Q3, the other end of the pull-down resistor R5, the second end of the field effect transistor Q2 and the second end of the field effect transistor Q3 are all grounded, and the single-chip microcomputer, the first end of the field effect transistor Q1, the third end of the field effect transistor Q1 and the third end of the field effect transistor Q2 are all electrically connected with the multi-channel power supply. The second end of the field effect transistor Q1 is electrically connected with the third end of the field effect transistor Q3. According to the utility model, the fast response time of high voltage switching can be realized, and a high reliability function is brought to a product.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, in particular to a fast high-voltage drive circuit. Background Art

[0002] High-voltage drive circuit switches are an important part of active communication products. As communication equipment places higher demands on the reliability of communication products, the development of fast high-voltage drive circuit switches is an inevitable trend, and greater requirements are placed on the response speed and stability of high-voltage drive switches in communication products.

[0003] In the existing technology, the high-voltage drive circuit composed of field-effect transistors is relatively common, so it is simple to implement and low-cost. Its principle has the following two schemes:

[0004] The first is to use a single-chip microcomputer to implement a high-voltage drive circuit switch solution, such as Figure 4 As shown, the circuit is composed of a single-chip microcomputer, a high-voltage driver, and a main power supply. The single-chip microcomputer outputs high and low level functions to provide high and low levels for the high-voltage drive circuit switch to achieve high-voltage output and cutoff. It is currently used in active communication products. From a technical perspective, this solution is more preferred, but in terms of cost control, the price is relatively expensive.

[0005] The second is the field effect tube to realize the high voltage drive circuit switch solution, such as Figure 5 As shown, resistors and field effect tubes are used to realize the opening and closing of high voltage. The circuit can be N+1. TTL level is the output of the microcontroller. When TTL=1, field effect tubes Q2 and Q3 are turned on, and field effect tube Q1 is turned off; when TTL=0, field effect tube Q1 is turned on, and field effect tubes Q2 and Q3 are turned off. Based on the switch control of the triode, the response time of the field effect tube has been greatly improved, which can better improve the performance of communication products. From a technical point of view, the field effect tube in this solution bears less current than the triode, and the field effect tube passing through the high voltage is easily damaged.

[0006] Therefore, it is necessary to propose a fast high-voltage drive circuit, add protection devices to the field effect transistor, meet the application parameters, protect the circuit devices from being damaged by high voltage current, and provide a faster response time for the high-voltage drive circuit. Utility Model Content

[0007] The purpose of the utility model is to provide a fast high-voltage drive circuit, which can achieve faster response time by switching high-voltage voltage, and bring high reliability function to the product.

[0008] To achieve this purpose, the utility model adopts the following technical solutions:

[0009] A fast high-voltage driving circuit includes a field effect transistor Q1, a field effect transistor Q2, a field effect transistor Q3 and a pull-down resistor R5;

[0010] One end of the pull-down resistor R5 is electrically connected to the single-chip computer, the first end of the field effect transistor Q2 and the first end of the field effect transistor Q3 respectively, the other end of the pull-down resistor R5, the second end of the field effect transistor Q2 and the second end of the field effect transistor Q3 are all grounded, the single-chip computer, the first end of the field effect transistor Q1, the third end of the field effect transistor Q1 and the third end of the field effect transistor Q2 are all electrically connected to the multi-channel power supply, and the second end of the field effect transistor Q1 is electrically connected to the third end of the field effect transistor Q3;

[0011] The multi-channel power supply provides the operating voltage VBB IN for the single-chip microcomputer and the field effect transistor Q1, and the single-chip microcomputer is used to switch the TTL level;

[0012] When the field effect transistor Q1 is in the on state, the second end of the field effect transistor Q1 outputs the driving voltage VBBOUT, and the field effect transistor Q2 and the field effect transistor Q3 are in the off state;

[0013] When the field effect transistor Q1 is in a cut-off state, the field effect transistor Q2 and the field effect transistor Q3 are in a conduction state.

[0014] Preferably, a diode D1 is further included, wherein the anode of the diode D1 is electrically connected to the third end of the field effect transistor Q2 and the multi-channel power supply respectively, and the cathode of the diode D1 is electrically connected to the second end of the field effect transistor Q1 and the third end of the field effect transistor Q3 respectively.

[0015] Preferably, the field effect transistor Q1, the field effect transistor Q2 and the field effect transistor Q3 are all N-channel junction field effect transistors.

[0016] Preferably, it also includes a bias resistor R1 and a bias resistor R2;

[0017] One end of the bias resistor R1 and one end of the bias resistor R2 are electrically connected to the multi-channel power supply respectively;

[0018] The other end of the bias resistor R1 is electrically connected to the third end of the field effect transistor Q2 and the first end of the field effect transistor Q1 respectively;

[0019] The other end of the bias resistor R2 is electrically connected to the third end of the field effect transistor Q1.

[0020] Preferably, the resistance of the bias resistor R1 is greater than the resistance of the bias resistor R2.

[0021] Preferably, it also includes a bias resistor R3 and a bias resistor R4;

[0022] One end of the bias resistor R3 and one end of the bias resistor R4 are electrically connected to one end of the pull-down resistor R5 respectively;

[0023] The other end of the bias resistor R3 is electrically connected to the first end of the field effect transistor Q2;

[0024] The other end of the bias resistor R4 is electrically connected to the first end of the field effect transistor Q3.

[0025] One of the above technical solutions has the following beneficial effects:

[0026] When the external single-chip microcomputer performs TTL level switching and the TTL level is 0, there is no high level input to the first terminal of the field effect tube Q2 and the field effect tube Q3. At this time, it is in the cut-off state. The VBB IN voltage passes through the first terminal of the field effect tube Q2. At this time, the field effect tube Q1 is in the on state, and the second terminal of the field effect tube Q1 has the VBB OUT voltage output. Figure 2 As shown, the voltage turn-on time is 5.4μs.

[0027] When the external single-chip microcomputer performs TTL level switching and the TTL level is 1, the first terminal of the field effect tube Q2 and the field effect tube Q3 has a high level 3.3Vcc input, and it is in the on state. Since the field effect tube Q2 is turned on, there is a voltage difference between the first terminal and the third terminal of the field effect tube Q1, and the field effect tube Q1 is cut off. At this time, the whole circuit is in the off state. Figure 3 As shown, the turn-off time is 400ns.

[0028] When the TTL level is not selected, due to the pull-down resistor R5, the TTL defaults to a low level, and the working state is consistent with when the TTL level is 0, which can effectively improve the reliability of the high-voltage drive circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a circuit diagram of a fast high-voltage drive circuit of the utility model;

[0030] Figure 2 This is a schematic diagram of the output of a high-voltage drive circuit realizing the principle of the utility model;

[0031] Figure 3 This is a cut-off schematic diagram of high-voltage drive of a fast high-voltage drive circuit of the utility model;

[0032] Figure 4 It is a schematic diagram of the principle of the high-voltage drive circuit switch scheme implemented by the prior art single-chip microcomputer;

[0033] Figure 5 It is a schematic diagram of the principle of realizing a high-voltage drive circuit switch solution using a field effect tube in the prior art. DETAILED DESCRIPTION

[0034] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, the meaning of "plurality" is two or more.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] like Figure 1 As shown, a fast high-voltage driving circuit includes a field effect transistor Q1, a field effect transistor Q2, a field effect transistor Q3 and a pull-down resistor R5;

[0039] One end of the pull-down resistor R5 is electrically connected to the single-chip computer, the first end of the field effect transistor Q2 and the first end of the field effect transistor Q3 respectively, the other end of the pull-down resistor R5, the second end of the field effect transistor Q2 and the second end of the field effect transistor Q3 are all grounded, the single-chip computer, the first end of the field effect transistor Q1, the third end of the field effect transistor Q1 and the third end of the field effect transistor Q2 are all electrically connected to the multi-channel power supply, and the second end of the field effect transistor Q1 is electrically connected to the third end of the field effect transistor Q3;

[0040] The multi-channel power supply provides the operating voltage VBB IN for the single-chip microcomputer and the field effect transistor Q1, and the single-chip microcomputer is used to switch the TTL level;

[0041] When the field effect transistor Q1 is in the on state, the second end of the field effect transistor Q1 outputs the driving voltage VBBOUT, and the field effect transistor Q2 and the field effect transistor Q3 are in the off state;

[0042] When the field effect transistor Q1 is in a cut-off state, the field effect transistor Q2 and the field effect transistor Q3 are in a conduction state.

[0043] In this embodiment, the single-chip microcomputer and the high-voltage drive circuit are powered by a multi-channel power supply, as shown in FIG. Figure 1 shown.

[0044] When the external single-chip microcomputer performs TTL level switching and the TTL level is 0, there is no high level input to the first terminal of the field effect tube Q2 and the field effect tube Q3. At this time, it is in the cut-off state. The VBB IN voltage passes through the first terminal of the field effect tube Q2. At this time, the field effect tube Q1 is in the on state, and the second terminal of the field effect tube Q1 has the VBB OUT voltage output. Figure 2 As shown, the voltage turn-on time is 5.4μs.

[0045] When the external single-chip microcomputer performs TTL level switching and the TTL level is 1, the first terminal of the field effect tube Q2 and the field effect tube Q3 has a high level 3.3Vcc input, and it is in the on state. Since the field effect tube Q2 is turned on, there is a voltage difference between the first terminal and the third terminal of the field effect tube Q1, and the field effect tube Q1 is cut off. At this time, the whole circuit is in the off state. Figure 3 As shown, the turn-off time is 400ns.

[0046] When the TTL level is not selected, due to the pull-down resistor R5, the TTL defaults to a low level, and the working state is consistent with when the TTL level is 0, which can effectively improve the reliability of the high-voltage drive circuit.

[0047] As described above, the utility model realizes the fast switching function of the high-voltage switch, and the total switching time is within 6 μs.

[0048] Further description, it also includes a diode D1, the anode of the diode D1 is electrically connected to the third end of the field effect transistor Q2 and the multi-channel power supply, and the cathode of the diode D1 is electrically connected to the second end of the field effect transistor Q1 and the third end of the field effect transistor Q3.

[0049] In this embodiment, a diode D1 is added. In the actual working process, the field effect transistor Q1 is easily broken down by the reverse bias voltage. In order to protect the field effect transistor Q1, the diode D1 is added.

[0050] Further explanation, the field effect transistor Q1, the field effect transistor Q2 and the field effect transistor Q3 are all N-channel junction field effect transistors. It should be noted that the first end of the field effect transistor Q1, the first end of the field effect transistor Q2 and the first end of the field effect transistor Q are all gates, the second end of the field effect transistor Q1, the second end of the field effect transistor Q2 and the second end of the field effect transistor Q are all sources, and the third end of the field effect transistor Q1, the third end of the field effect transistor Q2 and the third end of the field effect transistor Q are all drains.

[0051] Further explanation, bias resistor R1 and bias resistor R2 are also included;

[0052] One end of the bias resistor R1 and one end of the bias resistor R2 are electrically connected to the multi-channel power supply respectively;

[0053] The other end of the bias resistor R1 is electrically connected to the third end of the field effect transistor Q2 and the first end of the field effect transistor Q1 respectively;

[0054] The other end of the bias resistor R2 is electrically connected to the third end of the field effect transistor Q1.

[0055] In this embodiment, the bias resistor R1 and the bias resistor R2 are respectively the input resistors of the first and third terminals of the field effect transistor Q1 , and their main function is isolation to prevent the external input voltage from affecting the operation of the field effect transistor Q1 .

[0056] To further illustrate, the resistance of the bias resistor R1 is greater than the resistance of the bias resistor R2.

[0057] Since the gate (corresponding to the first terminal) and the source (corresponding to the third terminal) of the field effect transistor Q1 require different bias voltages, the different resistance values ​​of the bias resistor R1 and the bias resistor R2 can ensure that the correct bias voltage is provided for the two terminals.

[0058] Further explanation, bias resistor R3 and bias resistor R4 are also included;

[0059] One end of the bias resistor R3 and one end of the bias resistor R4 are electrically connected to one end of the pull-down resistor R5 respectively;

[0060] The other end of the bias resistor R3 is electrically connected to the first end of the field effect transistor Q2;

[0061] The other end of the bias resistor R4 is electrically connected to the first end of the field effect transistor Q3.

[0062] In this embodiment, the bias resistor R3 and the bias resistor R4 are the input resistors of the first end of the field effect transistor Q2 and the first end of the field effect transistor Q3, respectively. Their main function is to isolate and prevent the external input voltage from affecting the operation of the field effect transistor Q2 and the field effect transistor Q3, thereby ensuring that the field effect transistor Q2 and the field effect transistor Q3 operate normally.

[0063] The technical principle of the present invention is described above in combination with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations here, technicians in this field can think of other specific implementations of the present invention without creative work, and these equivalent variations or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A fast high-voltage drive circuit, characterized in that: It includes a field effect transistor Q1, a field effect transistor Q2, a field effect transistor Q3 and a pull-down resistor R5; One end of the pull-down resistor R5 is electrically connected to the single-chip computer, the first end of the field effect transistor Q2 and the first end of the field effect transistor Q3 respectively, the other end of the pull-down resistor R5, the second end of the field effect transistor Q2 and the second end of the field effect transistor Q3 are all grounded, the single-chip computer, the first end of the field effect transistor Q1, the third end of the field effect transistor Q1 and the third end of the field effect transistor Q2 are all electrically connected to the multi-channel power supply, and the second end of the field effect transistor Q1 is electrically connected to the third end of the field effect transistor Q3; The multi-channel power supply provides the operating voltage VBB IN for the single-chip microcomputer and the field effect transistor Q1, and the single-chip microcomputer is used to switch the TTL level; When the field effect transistor Q1 is in the on state, the second end of the field effect transistor Q1 outputs the driving voltage VBB OUT, and the field effect transistor Q2 and the field effect transistor Q3 are in the off state; When the field effect transistor Q1 is in a cut-off state, the field effect transistor Q2 and the field effect transistor Q3 are in a conduction state.

2. A fast high-voltage drive circuit according to claim 1, characterized in that: It also includes a diode D1, the anode of the diode D1 is electrically connected to the third end of the field effect tube Q2 and the multi-channel power supply, and the cathode of the diode D1 is electrically connected to the second end of the field effect tube Q1 and the third end of the field effect tube Q3.

3. A fast high-voltage drive circuit according to claim 2, characterized in that: The field effect transistor Q1, field effect transistor Q2 and field effect transistor Q3 are all N-channel junction field effect transistors.

4. A fast high-voltage drive circuit according to claim 3, characterized in that: Also includes a bias resistor R1 and a bias resistor R2; One end of the bias resistor R1 and one end of the bias resistor R2 are electrically connected to the multi-channel power supply respectively; The other end of the bias resistor R1 is electrically connected to the third end of the field effect transistor Q2 and the first end of the field effect transistor Q1 respectively; The other end of the bias resistor R2 is electrically connected to the third end of the field effect transistor Q1.

5. A fast high-voltage driving circuit according to claim 4, characterized in that: The resistance value of the bias resistor R1 is greater than the resistance value of the bias resistor R2.

6. A fast high-voltage driving circuit according to claim 5, characterized in that: Also includes a bias resistor R3 and a bias resistor R4; One end of the bias resistor R3 and one end of the bias resistor R4 are electrically connected to one end of the pull-down resistor R5 respectively; The other end of the bias resistor R3 is electrically connected to the first end of the field effect transistor Q2; The other end of the bias resistor R4 is electrically connected to the first end of the field effect transistor Q3.

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