A driving circuit

Abstract

The present application discloses a drive circuit, comprising a power supply, a control module, an improvement module, and a push-pull module. The control module is configured to receive direct current (DC) from the power supply and output a first drive signal to the push-pull module. The push-pull module is configured to amplify the first drive signal output by the control module and output the amplified second drive signal to a driven load. The input end of the improvement module is connected to the output end of the power supply, and the output end is connected to the push-pull module, thereby reducing the conduction voltage drop of power devices in the push-pull module. This reduces the heat generated by the power devices in the push-pull module during operation, thereby improving the load capacity of the drive circuit and reducing costs.

Description

Technical Field

[0001] The present application relates to the field of electronic power technology, and in particular to a driving circuit. Background Art

[0002] Currently, traditional drive circuits often use a push-pull structure with an isolation transformer to drive switching devices. The push-pull circuit amplifies the square wave signal from the PWM chip, isolates it through a drive isolation transformer, and outputs a powered and isolated signal to drive switching devices such as IGBTs. Traditional push-pull drive circuits have limited load capacity, and typically only one drive isolation transformer is used for each push-pull circuit. When the load on the push-pull circuit increases, the top P-tube in the push-pull structure heats up, seriously affecting its lifespan and circuit operation.

[0003] In the related art, multiple sets of driving push-pull circuits are usually used to drive several driving isolation transformers, but this increases the cost of the driving circuit. Summary of the Invention

[0004] The main purpose of this application is to provide a driving circuit to reduce the heat generated by the power devices in the push-pull module during operation by improving the module, thereby improving the load capacity of the driving circuit and reducing costs.

[0005] To achieve the above-mentioned purpose, the present application provides a driving circuit, including a power supply, a control module, an improvement module and a push-pull module; wherein,

[0006] The control module is used to receive the direct current output by the power supply and output a first driving signal to the push-pull module;

[0007] The push-pull module is used to strengthen the first driving signal output by the control module and output the second driving signal obtained after strengthening to the driving load;

[0008] The input end of the improvement module is connected to the output end of the power supply, and the output end is connected to the push-pull module, which is used to reduce the conduction voltage drop of the power device in the push-pull module.

[0009] Optionally, the push-pull module includes a first transistor and a second transistor; wherein, the base of the first transistor is connected to the control module, the collector is connected to the output end of the improvement module, and the emitter is connected to the emitter of the second transistor, and the improvement module is used to reduce the conduction voltage drop between the base and the emitter of the first transistor; the base of the second transistor is connected to the control module, and the collector is connected to the ground end; a first node is formed between the emitter of the first transistor and the emitter of the second transistor, and the second drive signal is output to the drive load through the first node.

[0010] Optionally, the improvement module includes a first diode and a second diode; wherein the anode of the first diode is connected to the output end of the power supply, and the cathode is connected to the anode of the second diode; and the cathode of the second diode is connected to the collector of the first transistor.

[0011] Optionally, the driving circuit further includes a first capacitor module, one end of the first capacitor module is connected to the output end of the improvement module, and the other end is connected to the ground end, and the first capacitor module is used to filter the signal of the push-pull module.

[0012] Optionally, the driving circuit further includes a second capacitor module, one end of the second capacitor module is connected to the output end of the power supply, and the other end is connected to the ground end, for filtering the direct current output by the power supply.

[0013] Optionally, the control module includes a control chip, an input protection circuit, and a drive module, and the control chip includes a power supply input pin, a drive output pin, and a compensation pin; wherein, the power supply input pin of the control chip is used to receive the DC power output by the power supply, and output a first drive signal to the push-pull module through the drive output pin; the input end of the input protection circuit is connected to the compensation pin of the control chip, and the output end is connected to the ground end, which is used to prevent the drive circuit from being damaged due to excessive voltage; one end of the drive module is connected to the drive output pin of the control chip, and the other end is connected to the push-pull module, which is used to stabilize the first drive signal output by the control chip; the power supply and the ground end form a second node, and the power supply input pin of the control chip is connected to the second node.

[0014] Optionally, the input protection circuit includes a first resistor and a first capacitor; the first resistor and the first capacitor are connected in parallel.

[0015] Optionally, the driving module includes a first driving resistor and a second driving resistor; wherein, one end of the first driving resistor is connected to the driving output pin of the control chip, and the other end of the first driving resistor is connected to the base of the first transistor of the push-pull module; one end of the second driving resistor is connected to the driving output pin of the control chip, and the other end of the second driving resistor is connected to the base of the second transistor of the push-pull module.

[0016] Optionally, the control module further includes a soft start loop: one end of the soft start loop is connected to the compensation pin of the control chip, and the other end is connected to the voltage reference pin of the control chip, wherein the soft start loop is used to control the power-on rate of the control chip.

[0017] Optionally, the driving load includes a plurality of isolation transformers connected in parallel.

[0018] The driving circuit of the present application includes: a control module for receiving the direct current output by the power supply and outputting a first driving signal to the push-pull module; a push-pull module for strengthening the first driving signal output by the control module and outputting the second driving signal obtained after strengthening to the driving load; an improvement module, the input end of which is connected to the output end of the power supply and the output end of which is connected to the push-pull module, for reducing the conduction voltage drop of the power device in the push-pull module. The present application utilizes the improvement module to reduce the conduction voltage drop of the power device in the push-pull module, thereby reducing the heat generation of the power device in the push-pull module, extending the service life of the device, and improving the stability of the circuit. In addition, the introduction of the improvement module can avoid solving the problem of heat generation by designing multiple sets of push-pull modules, thereby reducing costs while improving the load capacity of the driving circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is one of the circuit diagrams of the driving circuit of an embodiment of the present application;

[0020] Figure 2 This is the second circuit diagram of the driving circuit of the embodiment of the present application;

[0021] Figure 3 This is the third circuit diagram of the driving circuit of the embodiment of the present application;

[0022] Figure 4 This is the fourth circuit diagram of the driving circuit of the embodiment of the present application;

[0023] Figure 5 This is the fifth circuit diagram of the driving circuit of the embodiment of the present application;

[0024] Figure 6 This is the sixth circuit diagram of the driving circuit according to the embodiment of the present application.

[0025] In the figure, 100 is a power supply; 200 is a control module; 201 is a control chip; 202 is an input protection circuit; 203 is a driving module; 300 is an improvement module; 400 is a push-pull module; 501 is a first capacitor module; and 502 is a second capacitor module.

[0026] The realization of the objectives, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of this application more clear, the technical solutions in this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0028] If the embodiments of the present invention include descriptions of "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include at least one of such features.

[0029] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0030] A push-pull circuit typically consists of two transistors: an upper transistor (P transistor), either PNP or PMOS, responsible for supplying current from the power supply to the load; and a lower transistor (N transistor), either NPN or NMOS, responsible for pulling the load current to ground. Currently, traditional drive circuits often use a push-pull structure with an isolation transformer to drive switching devices. The push-pull circuit amplifies the square wave signal generated by the PWM chip, isolates it through a drive isolation transformer, and outputs a powered and isolated signal to drive switching devices such as IGBTs.

[0031] Traditional push-pull circuits have limited load capacity. Typically, each drive circuit is equipped with only one isolation transformer. When the load on the push-pull circuit increases, the top P-tube in the push-pull structure generates heat, seriously affecting device life and circuit operation. Specifically, when a traditional push-pull structure is heavily loaded (i.e., with multiple drive transformers), the transformers' inherent hysteresis and eddy current losses, combined with the losses of multiple isolation transformers connected in parallel, can severely interfere with the square wave input signal of the PWM chip, causing the input signal to be pulled down and, in more severe cases, even distorted. Consequently, the high level of the push-pull input signal will be lower than the supply voltage at its upper end, increasing the voltage difference between the base and emitter of the top P-tube. Furthermore, under heavy load, the current flowing through the top P-tube is the sum of the currents flowing through the multiple isolation transformers. This increased voltage difference and the high total current significantly increase the power consumption of the top P-tube, which is the primary cause of heat generation.

[0032] In the related art, multiple sets of driving push-pull circuits are used to drive several driving isolation transformers, but this increases the cost of the driving circuit.

[0033] To this end, embodiments of the present application provide a driver circuit that utilizes an improved module to reduce the conduction voltage drop of the power devices in the push-pull module. This reduces heat generation in the power devices (i.e., the upper P-tube) in the push-pull module, extending the device's service life and improving circuit stability. Furthermore, the introduction of the improved module avoids the need to design multiple push-pull modules to address heat generation issues, thereby increasing the driver circuit's load capacity while reducing costs.

[0034] Figure 1 This is one of the circuit diagrams of the driving circuit in the embodiment of the present application.

[0035] like Figure 1 As shown, the driving circuit may include a power supply 100, a control module 200, an improvement module 300, and a push-pull module 400. The control module 200 is configured to receive the DC power output by the power supply 100 and output a first driving signal to the push-pull module 400. The push-pull module 400 is configured to amplify the first driving signal output by the control module 200 and output the amplified second driving signal to the driving load. The input end of the improvement module 300 is connected to the output end of the power supply 100, and the output end is connected to the push-pull module 400, thereby reducing the conduction voltage drop of the power devices in the push-pull module 400.

[0036] First, it should be noted that the power supply 100 of this embodiment can be at least 12V DC. The following explanation of this application uses 12V DC as an example, but does not limit the specific value of DC itself. Furthermore, the letters used in this embodiment to describe the various modules and components in the circuit are exemplary and should not limit the scope of this application.

[0037] The control module 200 may also be used to determine whether the input voltage of the circuit is stable, the frequency is fixed, etc.

[0038] The push-pull module 400 may also be referred to as a push-pull circuit, a push-pull structure, etc. In a possible implementation, the push-pull module 400 may be a totem pole push-pull module.

[0039] It is understandable that after 12V DC is input into control module 200, the control chip in control module 200 oscillates and generates a wave. After the signal is amplified by push-pull module 400, the drive signal of the drive transformer can drive the load. However, as the driven load increases, that is, as the number of driven transformers increases, the transformer's inherent losses increase, resulting in a decrease in the drive voltage and an increase in power consumption of the push-pull module 400, which manifests as external heat. This reduces the service life of the push-pull module 400 and increases the risk of drive failure due to damage to the push-pull module 400.

[0040] Based on this, the present application designs an improved module 300, which uses the improved module 300 to reduce the voltage drop generated by the power devices of the push-pull module 400 during operation, thereby reducing the heat generation of the power devices in the push-pull module 400, extending the service life of the devices, and improving the stability of the circuit.

[0041] In one possible implementation, the above-mentioned driving load may include multiple isolation transformers connected in parallel; it should be understood that the above-mentioned driving load is only an example, and the driving circuit involved in this application can also be applied to other driving scenarios, and this application does not limit this.

[0042] Figure 2 This is the second circuit diagram of the driving circuit according to the embodiment of the present application.

[0043] like Figure 2 As shown, in some embodiments, the push-pull module 400 may include a first transistor (denoted as Q1 in the figure) and a second transistor (denoted as Q2 in the figure); wherein the base of the first transistor is connected to the control module 200, the collector is connected to the output end of the improvement module 300, and the emitter is connected to the emitter of the second transistor, and the improvement module 300 is used to reduce the conduction voltage drop between the base and the emitter of the first transistor; the base of the second transistor is connected to the control module 200, and the collector is connected to the ground end; a first node is formed between the emitter of the first transistor and the emitter of the second transistor, and the second drive signal is output to the drive load through the first node.

[0044] In this embodiment, the first transistor may be a positive-negative-positive bipolar junction transistor (PNP transistor), and the second transistor may be a negative-positive-negative bipolar junction transistor (NPN transistor). It should be noted that the specific models of the first and second transistors are merely examples and are not intended to limit the specific models of the first and second transistors.

[0045] Specifically, the push-pull module 400 realizes logic level conversion and strong current driving by alternately conducting the first transistor and the second transistor. Its core functions include signal enhancement, driving capability improvement, fast switching and level adaptation.

[0046] Optionally, when the first transistor is turned on, its collector-emitter voltage (Vce(sat)) is typically 0.2V to 0.4V (for silicon transistors). At high currents (e.g., above 1A), the power consumption of the first transistor increases significantly, leading to excessive temperature rise or even damage. Therefore, by adding the improvement module 300 to distribute the voltage difference (expressed as Vbe) between the base and emitter of the first transistor, the voltage between the base and emitter of the first transistor is reduced. This reduces the voltage drop across the first transistor itself, thereby reducing heat generation.

[0047] This application proposes an improved design that optimizes circuit performance by dynamically adjusting the base-emitter voltage of the first transistor. Its core goal is to reduce the saturation voltage drop and heat generation of the first transistor while minimizing the attenuation of the drive signal and improving the drive load capacity.

[0048] Figure 3 This is the third circuit diagram of the driving circuit according to the embodiment of the present application.

[0049] like Figure 3 As shown, in some embodiments, the improvement module 300 may include a first diode (denoted as D3 in the figure) and a second diode (denoted as D4 in the figure); wherein the anode of the first diode is connected to the output end of the power supply, and the cathode is connected to the anode of the second diode; and the cathode of the second diode is connected to the collector of the first transistor.

[0050] In this embodiment, an improvement module 300 consisting of a first diode and a second diode connected in series is added at the input of the push-pull module 400. The voltage drop generated when the first diode and the second diode are forward-conducted is used to share the voltage difference between the base and the emitter of the first transistor in the push-pull module 400, thereby reducing the heat generated by the first transistor in the push-pull module 400.

[0051] Furthermore, since the forward conduction voltage drop of the diode is very small, while reducing the heating of the first transistor in the push-pull module 400, the attenuation of the driving signal is avoided to the minimum extent, thereby increasing the load capacity of the driver.

[0052] Figure 4 This is the fourth circuit diagram of the driving circuit according to the embodiment of the present application.

[0053] like Figure 4 As shown, in some embodiments, the driving circuit may further include a first capacitor module 501 , one end of the first capacitor module 501 being connected to the output end of the improvement module 300 and the other end being connected to the ground end. The first capacitor module 501 is used to filter the signal of the push-pull module 400 .

[0054] In this embodiment, the first capacitor module 501 may include at least two push-pull circuit filter capacitors connected in parallel. It should be noted that push-pull circuit filter capacitors are key components for optimizing circuit performance and improving stability. They have functions such as suppressing high-frequency noise, smoothing drive signals, reducing switching losses, and preventing oscillation.

[0055] For example, in push-pull module 400, the rapid switching of NPN and PNP transistors generates sudden changes in di / dt and dv / dt, triggering high-frequency oscillations (e.g., glitches in the 10MHz to 100MHz range). The push-pull loop filter capacitor presents low impedance to high-frequency signals, shorting the noise to ground or the power supply, preventing interference with subsequent circuits. Furthermore, the charge and discharge levels of the push-pull loop filter capacitor smooth out voltage fluctuations, reducing electromagnetic interference (EMI).

[0056] The push-pull loop filter capacitor can significantly reduce the heating problem of NPN and PNP transistors in the push-pull module by optimizing signal quality, suppressing switching noise, and stabilizing the power supply voltage.

[0057] Continue to refer Figure 4 In some embodiments, the driving circuit may further include a second capacitor module 502 , one end of which is connected to the output end of the power supply 100 , and the other end is connected to the ground end, for filtering the DC power output by the power supply 100 .

[0058] In this embodiment, the second capacitor module 502 may include at least two filter capacitors connected in parallel. In this embodiment, the second capacitor module 502 may also serve as a decoupling network to improve the transient response capability of the DC input. When the output current of the power supply 100 suddenly changes, the second capacitor module 502 can discharge to maintain voltage stability.

[0059] Figure 5 This is the fifth circuit diagram of the driving circuit according to the embodiment of the present application.

[0060] like Figure 5 As shown, in some embodiments, the control module 200 may include a control chip 201; the control chip 201 may include a power supply input pin and a drive output pin, wherein the power supply input pin of the control chip 201 is used to receive the direct current output by the power supply 100, and output a first drive signal to the push-pull module 400 through the drive output pin; the power supply 100 and the ground terminal form a second node, and the power supply input pin of the control chip 201 is connected to the second node.

[0061] Optionally, the control chip 201 may be a PWM control chip UC2845. It should be noted that this is only an illustrative example and does not limit the specific model of the control chip 201.

[0062] It should be understood that the power supply input pin of the control chip 201 can specifically be the power supply pin VCC of the control chip 201 (ie Figure 6 The driving output pin of the control chip 201 can be specifically the PWM wave output pin OUT (i.e. Figure 6 Pin 6 in the control chip shown).

[0063] like Figure 5 As shown, in some embodiments, the control chip 201 may further include a compensation pin, and the control module 200 may further include an input protection circuit 202, wherein the input end of the input protection circuit 202 is connected to the compensation pin of the control chip, and the output end is connected to the ground end, so as to prevent the driving circuit from being damaged due to excessive voltage.

[0064] It should be understood that the compensation pin of the control chip 201 may specifically be the error amplifier compensation pin COMP of the control chip 201 (ie Figure 6 Pin 1 of the control chip shown in the figure) is connected to the compensation network (i.e., RC circuit) to stabilize the feedback loop.

[0065] In some embodiments, the input protection circuit 202 may include a first resistor R1 and a first capacitor C2 , where the first resistor R1 and the first capacitor C2 are connected in parallel.

[0066] In this embodiment, the first resistor R1 may be a discharge resistor. It should be noted that this is only an illustrative example and does not limit the specific model of the first resistor R1.

[0067] It should be understood that first capacitor C2 is connected between the compensation pin of control chip 201 and ground (GND). This allows the control chip to start pulsating after the system is powered on, and the voltage at the compensation pin gradually increases until it reaches the reference voltage. However, due to the presence of C2 in the input protection circuit, the startup voltage first charges first capacitor C2 before charging control chip 201. This effectively prolongs the process from powering up control chip 201 to pulsating, ensuring safe operation of control chip 201 at the moment of startup. Furthermore, because R1 in the input protection circuit acts as a discharge resistor, C2 can be quickly discharged after the system loses power.

[0068] like Figure 5 As shown, in some embodiments, the control module 200 may further include a driving module 203, one end of which is connected to the driving output pin of the control chip 201, and the other end is connected to the push-pull module 400, for stabilizing the first driving signal output by the control chip 201 and limiting the driving current.

[0069] In some embodiments, the driving module 203 may include a first driving resistor R5 and a second driving resistor R6; wherein, one end of the first driving resistor R5 is connected to the driving output pin of the control chip 201, and the other end of the first driving resistor R5 is connected to the base of the first transistor Q1 of the push-pull module 400; one end of the second driving resistor R6 is connected to the driving output pin of the control chip 201, and the other end of the second driving resistor R6 is connected to the base of the second transistor Q2 of the push-pull module 400.

[0070] It should be understood that the first driving resistor R5 and the second driving resistor R6 are connected in parallel to the control module 200 and respectively drive the bases of the first transistor Q1 and the second transistor Q2 in the push-pull module 400 .

[0071] It should be understood that the design of the present application optimizes base current distribution, balances switching speed, and improves circuit stability while avoiding the limitations of traditional series resistors.

[0072] like Figure 5 As shown, in some embodiments, the control module 200 may further include a soft start circuit, and the control chip 201 may further include a voltage reference pin: one end of the soft start circuit is connected to the compensation pin of the control chip 201, and the other end is connected to the voltage reference pin of the control chip 201, wherein the soft start circuit is used to control the rate at which the control chip 201 is powered on. Specifically, the soft start circuit can prevent the control chip from being damaged by current shock by controlling the current rise rate when the control chip 201 is powered on, that is, the control chip will not be damaged by current shock at the moment the protection circuit is powered on.

[0073] It should be understood that the voltage reference pin of the control chip 201 may specifically be the pin VREF (i.e. Figure 6 The VREF pin can provide a reference voltage for the external circuit.

[0074] It should be understood that when the entire system starts and the control chip 201 is powered, the voltage of the compensation pin will gradually increase until it is equal to the reference voltage sent by the voltage reference pin of the control chip 201, and then the control chip 201 starts to generate waveforms.

[0075] It should be understood that without a soft-start circuit, control chip 201 might immediately start at full power when the system is powered on, requiring the input power supply to instantly supply a large current. However, the soft-start circuit controls the power-up rate, gradually increasing the voltage on the compensation pin, preventing control chip 201 from immediately entering full-load operation. This prevents large inrush currents from being generated when power supply 100 is turned on, preventing the power supply system from being impacted by excessive inrush currents, protecting the power supply device and other circuit components from damage caused by high currents, and extending the service life of the device.

[0076] Figure 6 This is the sixth circuit diagram of the driving circuit according to the embodiment of the present application.

[0077] like Figure 6 As shown, in some embodiments, a node is formed between the soft-start circuit and the input protection circuit. The control module 200 may further include two diodes D1 and a capacitor C3 connected in series. The anode of the first of the two series-connected diodes D1 is connected to pin 1 of the control chip, the cathode of the first diode is connected to the anode of the second diode, and the cathode of the second diode is connected to the node formed between the soft-start circuit and the input protection circuit. One end of C3 is connected between the two diodes D1, and the other end is connected to ground. C3 is used to prevent diode D1 from floating.

[0078] In some embodiments, the control chip (i.e. Figure 6 U1 in FIG1 may also include a feedback voltage input pin VFB (i.e., pin 2), which is directly grounded. This pin is used to receive the output voltage sampling signal and compare it with the internal reference to adjust the PWM duty cycle.

[0079] In some embodiments, the control chip may further include a current detection pin ISNS (ie, pin 3), and the control module 200 may further include a resistor R2, one end of the resistor R2 being connected to pin 3 of the control chip and the other end being grounded.

[0080] In some embodiments, the control chip may further include a pin RT / CT (ie, pin 4 ), and the control module 200 may further include a capacitor C1 , one end of which is connected to pin 4 of the control chip and the other end is grounded.

[0081] In some embodiments, a node is formed between the resistor R2 and pin 3, and a node is formed between the capacitor C1 and pin 4. The control module 200 may further include resistors R3 and R4, wherein one end of R3 is connected to the node between the resistor R2 and pin 3, and the other end is connected to the node between the capacitor C1 and pin 4; one end of R4 is connected to the node between the capacitor C1 and pin 4, and the other end is connected to pin 8 of the control chip.

[0082] It should be noted that the pin RT / CT (i.e. pin 4) is used to connect an external resistor (RT) and capacitor (CT) to set the PWM frequency. Figure 6 As shown, in this embodiment, pin 4 is connected to resistor R4 and capacitor C1, which is used to determine the frequency of the PWM square wave emitted by the control chip.

[0083] It should be noted that the pin ISNS (i.e. pin 3) can be pulled down to ground through R2, and the resistor R3 can be used to protect the pin from rapid discharge when power is lost.

[0084] In some embodiments, the control chip may further include a pin GND (ie, pin 5 ), which is directly grounded.

[0085] In some embodiments, the control module 200 may further include a capacitor C4, which is a filter capacitor for the control chip power supply circuit. One end of C4 is connected to pin 7 of the control chip, and the other end is grounded.

[0086] In some embodiments, the control module 200 may further include a diode D2, the anode of which is grounded and the cathode of which is connected to the output terminal of the power supply 100. As an example, the diode D2 may be a 15V voltage regulator diode to prevent input overvoltage from damaging the control chip.

[0087] In some embodiments, the first capacitor module 501 may include two capacitors connected in parallel, such as Figure 6 C5 and C6 in the improvement module 300, wherein one end of C5 and C6 is connected to the cathode of D4 in the improvement module 300, and the other end is grounded; the second capacitor module 502 may include two capacitors in parallel, such as Figure 6 C7 and C8 in the circuit; wherein, one end of C7 and C8 is connected to the output end of the power supply 100 respectively, and the other end is grounded.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A driving circuit, characterized in that: It includes power supply, control module, improvement module and push-pull module; among them, The control module is used to receive the direct current output by the power supply and output a first driving signal to the push-pull module; The push-pull module is used to strengthen the first driving signal output by the control module and output the strengthened second driving signal to the driving load; the push-pull module includes a first transistor and a second transistor; wherein the base of the first transistor is connected to the control module, the collector is connected to the output end of the improvement module, and the emitter is connected to the emitter of the second transistor; the base of the second transistor is connected to the control module, and the collector is connected to the ground end; a first node is formed between the emitter of the first transistor and the emitter of the second transistor, and the second driving signal is output to the driving load through the first node; The input end of the improvement module is connected to the output end of the power supply, and the output end is connected to the push-pull module, which is used to reduce the conduction voltage drop between the base and the emitter of the first transistor; the improvement module includes a first diode and a second diode; wherein, the anode of the first diode is connected to the output end of the power supply, and the cathode is connected to the anode of the second diode; the cathode of the second diode is connected to the collector of the first transistor.

2. The driving circuit according to claim 1, wherein: The driving circuit further includes a first capacitor module, one end of which is connected to the output end of the improvement module, and the other end of which is connected to the ground end. The first capacitor module is used to filter the signal of the push-pull module.

3. The driving circuit according to claim 1, wherein: The driving circuit further includes a second capacitor module, one end of which is connected to the output end of the power supply, and the other end of which is connected to the ground end, for filtering the direct current output by the power supply.

4. The driving circuit according to claim 1, wherein: The control module includes a control chip, an input protection circuit, and a drive module. The control chip includes a power input pin, a drive output pin, and a compensation pin. The power supply input pin of the control chip is used to receive the direct current output by the power supply, and output the first driving signal to the push-pull module through the driving output pin; The input end of the input protection circuit is connected to the compensation pin of the control chip, and the output end is connected to the ground end, so as to prevent the drive circuit from being damaged due to excessive voltage; One end of the driving module is connected to the driving output pin of the control chip, and the other end is connected to the push-pull module, so as to stabilize the first driving signal output by the control chip; The power supply and the ground terminal form a second node, and the power supply input pin of the control chip is connected to the second node.

5. The driving circuit according to claim 4, wherein: The input protection circuit includes a first resistor and a first capacitor, and the first resistor and the first capacitor are connected in parallel.

6. The driving circuit according to claim 4, wherein: The driving module includes a first driving resistor and a second driving resistor; wherein, One end of the first driving resistor is connected to the driving output pin of the control chip, and the other end of the first driving resistor is connected to the base of the first transistor of the push-pull module; One end of the second driving resistor is connected to the driving output pin of the control chip, and the other end of the second driving resistor is connected to the base of the second transistor of the push-pull module.

7. The driving circuit according to claim 4, wherein: The control module further includes a soft start circuit, and the control chip further includes a voltage reference pin: One end of the soft start loop is connected to the compensation pin of the control chip, and the other end is connected to the voltage reference pin of the control chip, wherein the soft start loop is used to control the power-on rate of the control chip.

8. The driving circuit according to any one of claims 1 to 7, characterized in that: The driving load includes a plurality of isolation transformers connected in parallel.

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