Switching tube driving circuit and power supply

Abstract

The utility model provides a switching tube driving circuit and a power supply. The switching tube driving circuit comprises a driving transformer and at least one output driving module, the driving transformer comprises a primary winding and at least one secondary winding, the secondary windings are in one-to-one correspondence with the output driving modules; the primary winding is used for inputting differential signals; for any secondary winding, the first end of the secondary winding is connected with the first input end of the output driving module corresponding to the secondary winding, and the second end of the secondary winding is connected with the second input end of the output driving module corresponding to the secondary winding; and the first output end and the second output end of the output driving module corresponding to the secondary winding are used for outputting a switching tube driving signal corresponding to the secondary winding. Synchronous output of driving signals of multiple paths of switching tubes is realized by adopting the transformer, and common-mode interference is reduced and the stability of the driving signals is improved by adopting differential signals.

Description

Technical Field

[0001] The utility model relates to the technical field of switch tube driving, and in particular to a switch tube driving circuit and a power supply. Background Art

[0002] Power supply is an indispensable component of various electronic devices, and is usually implemented by switching tubes. In some circuits of the power supply, two switching tubes are usually required to be turned on and off at the same time, or two switching tubes are complementary to each other.

[0003] In the prior art, each switch tube is usually controlled independently, so each switch tube cannot achieve precise synchronization, which affects the performance of the power supply. Utility Model Content

[0004] The embodiments of the utility model provide a switch tube driving circuit and a power supply to solve the problem in the prior art that multiple switch tubes in a circuit are difficult to accurately synchronize.

[0005] In a first aspect, an embodiment of the utility model provides a switch tube driving circuit, comprising: a driving transformer and at least one output driving module; wherein the driving transformer comprises: a primary winding and at least one secondary winding; each secondary winding corresponds to each output driving module one by one;

[0006] The primary winding is used to input differential signals;

[0007] For any secondary winding, the first end of the secondary winding is connected to the first input end of the output driving module corresponding to the secondary winding, and the second end of the secondary winding is connected to the second input end of the output driving module corresponding to the secondary winding; the first output end and the second output end of the output driving module corresponding to the secondary winding are used to output the switch tube drive signal corresponding to the secondary winding.

[0008] Optionally, the output driving module includes: a voltage dividing unit, a switch unit, a first diode, a first voltage stabilizing diode, a first capacitor and an output filtering unit;

[0009] The first input end of the output driving module is respectively connected to the first end of the switch unit, the first end of the output filter unit and the first output end of the output driving module, and the second input end of the output driving module is respectively connected to the cathode of the first diode and the first end of the voltage dividing unit;

[0010] The second end of the switch unit is connected to the anode of the first diode, the anode of the first voltage-regulating diode and the first end of the first capacitor respectively, and the control end of the switch unit is connected to the second end of the voltage-dividing unit;

[0011] The cathode of the first voltage stabilizing diode, the second end of the first capacitor and the second end of the output filtering unit are all connected to the second output end of the output driving module.

[0012] Optionally, the voltage dividing unit further includes a third end; the third end of the voltage dividing unit is respectively connected to the second end of the switch unit, the anode of the first diode, the anode of the first voltage stabilizing diode and the first end of the first capacitor; the voltage dividing unit includes: a first resistor and a second resistor;

[0013] A first end of the first resistor is connected to a first end of the voltage dividing unit, and a second end of the first resistor is connected to a first end of the second resistor and a second end of the voltage dividing unit respectively;

[0014] The second end of the second resistor is connected to the third end of the voltage dividing unit.

[0015] Optionally, the switch unit includes: a third resistor and a first switch tube;

[0016] The first end of the first switch tube is connected to the first end of the switch unit through the third resistor, the second end of the first switch tube is connected to the second end of the switch unit, and the control end of the first switch tube is connected to the control end of the switch unit.

[0017] Optionally, the first switch tube is NMOS.

[0018] Optionally, the output filter unit includes: a second diode, a fourth resistor and a second capacitor;

[0019] An anode of the second diode is connected to a first end of the output filter unit, and a cathode of the second diode is connected to a second end of the output filter unit via a fourth resistor;

[0020] The second capacitor is connected in parallel with the fourth resistor.

[0021] Optionally, the output driving module further includes: a fifth resistor;

[0022] The first input terminal of the output driving module is respectively connected to the first terminal of the switch unit, the first terminal of the output filtering unit and the first output terminal of the output driving module through the fifth resistor.

[0023] Optionally, the output driving module further includes: a sixth resistor;

[0024] Two ends of the sixth resistor are respectively connected to the first input end of the output driving module and the second input end of the output driving module.

[0025] Optionally, the number of secondary windings is two;

[0026] The first end of the first secondary winding and the second end of the second secondary winding are terminals of the same name.

[0027] In a second aspect, an embodiment of the utility model provides a power supply, including the switch tube driving circuit provided in the first aspect of the embodiment of the utility model.

[0028] The embodiment of the utility model provides a switch tube drive circuit and power supply. The switch tube drive circuit includes: a drive transformer and at least one output drive module; wherein the drive transformer includes: a primary winding and at least one secondary winding; each secondary winding corresponds to each output drive module one by one; the primary winding is used to input a differential signal; for any secondary winding, the first end of the secondary winding is connected to the first input end of the output drive module corresponding to the secondary winding, and the second end of the secondary winding is connected to the second input end of the output drive module corresponding to the secondary winding; the first output end and the second output end of the output drive module corresponding to the secondary winding are used to output the switch tube drive signal corresponding to the secondary winding. The transformer in the embodiment of the utility model has multiple secondary windings, and the synchronous output of multiple switch tube drive signals is realized simultaneously through multiple secondary windings, and multiple switch tubes can be driven to act synchronously at the same time, so that each switch tube is accurately synchronized. At the same time, differential signals are used to reduce common mode interference and improve the stability of the drive signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0030] Figure 1 This is a circuit structure diagram of a switch tube driving circuit provided by an embodiment of the utility model;

[0031] Figure 2 This is a schematic diagram of the circuit structure of an output drive module provided by an embodiment of the utility model;

[0032] Figure 3 This is a circuit structure diagram of another switch tube driving circuit provided by an embodiment of the utility model;

[0033] Figure 4 This is a circuit schematic diagram of a switch tube driving circuit provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0034] In order to enable people in the technical field to better understand the present solution, the technical solution in the embodiment of the present solution will be clearly described below in conjunction with the drawings in the embodiment of the present solution. Obviously, the described embodiment is an embodiment of a part of the present solution, not all of the embodiments. Based on the embodiments in the present solution, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present solution.

[0035] The term "including" and any other variations in the specification and claims of this solution and the above drawings mean "including but not limited to", and is intended to cover non-exclusive inclusions and is not limited to the examples listed in the text. In addition, the terms "first" and "second" are used to distinguish different objects, not to describe a specific order.

[0036] The following is a detailed description of the implementation of the present invention in conjunction with the specific drawings:

[0037] Figure 1 This is a schematic diagram of a switch tube drive circuit provided by an embodiment of the utility model. Figure 1 The switch tube driving circuit includes: a driving transformer T1 and at least one output driving module 1; wherein the driving transformer T1 includes: a primary winding and at least one secondary winding; each secondary winding corresponds to each output driving module 1 one by one;

[0038] The primary winding is used to input differential signals;

[0039] For any secondary winding, the first end of the secondary winding is connected to the first input end of the output driving module 1 corresponding to the secondary winding, and the second end of the secondary winding is connected to the second input end of the output driving module 1 corresponding to the secondary winding; the first output end and the second output end of the output driving module 1 corresponding to the secondary winding are used to output the switch tube drive signal corresponding to the secondary winding.

[0040] In the embodiment of the utility model, the driving transformer T1 includes multiple secondary windings, through which multiple isolated, synchronous output of in-phase or anti-phase switch tube driving signals can be realized, and multiple switch tubes can be driven to act synchronously at the same time, so that each switch tube is accurately synchronized. At the same time, the primary side of the driving transformer T1 inputs a differential signal, reduces common mode interference, and improves the stability of the switch tube driving signal.

[0041] In one possible implementation, reference Figure 2 , the output driving module 1 may include: a voltage dividing unit 11, a switch unit 12, a first diode D1, a first voltage stabilizing diode Z1, a first capacitor C1 and an output filtering unit 13;

[0042] The first input end of the output driving module 1 is respectively connected to the first end of the switch unit 12, the first end of the output filtering unit 13 and the first output end of the output driving module 1, and the second input end of the output driving module 1 is respectively connected to the cathode of the first diode D1 and the first end of the voltage dividing unit 11;

[0043] The second end of the switch unit 12 is connected to the anode of the first diode D1, the anode of the first voltage-stabilizing diode Z1 and the first end of the first capacitor C1 respectively, and the control end of the switch unit 12 is connected to the second end of the voltage-dividing unit 11;

[0044] The cathode of the first voltage stabilizing diode Z1 , the second end of the first capacitor C1 , and the second end of the output filter unit 13 are all connected to the second output end of the output driving module 1 .

[0045] In the embodiment of the utility model, the differential signal can be a positive or negative signal. When the positive or negative signal switches, the secondary winding generates a peak voltage, and the switch unit 12 is turned on to prevent the output drive module 1 from outputting overvoltage. The voltage divider unit 11 is used to divide the peak voltage to prevent the switch unit 12 from being damaged by excessive voltage. The first voltage regulator diode Z1 is used for voltage clamping, and is used together with the second capacitor C2 to increase the switching speed of different levels of the switch tube drive signal.

[0046] In one possible implementation, reference Figure 4 , the voltage dividing unit 11 may further include a third end; the third end of the voltage dividing unit 11 is respectively connected to the second end of the switch unit 12, the anode of the first diode D1, the anode of the first voltage stabilizing diode Z1 and the first end of the first capacitor C1; the voltage dividing unit 11 may include: a first resistor R1 and a second resistor R2;

[0047] A first end of the first resistor R1 is connected to a first end of the voltage dividing unit 11, and a second end of the first resistor R1 is connected to a first end of the second resistor R2 and a second end of the voltage dividing unit 11 respectively;

[0048] The second end of the second resistor R2 is connected to the third end of the voltage dividing unit 11 .

[0049] The voltage dividing unit 11 uses resistor voltage division, which has a simple circuit structure, a small number of components and a low cost.

[0050] In one possible implementation, reference Figure 4 , the switch unit 12 may include: a third resistor R3 and a first switch tube Q1;

[0051] The first end of the first switch tube Q1 is connected to the first end of the switch unit 12 through the third resistor R3 , the second end of the first switch tube Q1 is connected to the second end of the switch unit 12 , and the control end of the first switch tube Q1 is connected to the control end of the switch unit 12 .

[0052] In a possible implementation, the first switch tube Q1 may be an NMOS.

[0053] In the embodiment of the utility model, NMOS is used to implement the switch unit 12. When there is a peak voltage, the first switch tube Q1 is turned on to prevent overvoltage from being output by the output drive module 1. During normal operation, the first switch tube Q1 is turned off, which does not affect the output of the normal switch tube drive signal.

[0054] In one possible implementation, reference Figure 4 , the output filter unit 13 may include: a second diode D2, a fourth resistor R4 and a second capacitor C2;

[0055] The anode of the second diode D2 is connected to the first end of the output filter unit 13, and the cathode of the second diode D2 is connected to the second end of the output filter unit 13 through the fourth resistor R4;

[0056] The second capacitor C2 is connected in parallel with the fourth resistor R4.

[0057] Since the first diode D1 is unidirectionally conductive, RCD filtering can be used in the embodiment of the utility model to achieve filtering of the switch tube drive signal.

[0058] In one possible implementation, reference Figure 4 , the output driving module 1 may further include: a fifth resistor R5;

[0059] The first input terminal of the output driving module 1 is respectively connected to the first terminal of the switch unit 12 , the first terminal of the output filtering unit 13 , and the first output terminal of the output driving module 1 through the fifth resistor R5 .

[0060] The fifth resistor R5 is connected in series in the path for current limiting.

[0061] In one possible implementation, reference Figure 4 , the output driving module 1 may further include: a sixth resistor R6;

[0062] Two ends of the sixth resistor R6 are connected to the first input end of the output driver module 1 and the second input end of the output driver module 1 respectively.

[0063] The sixth resistor R6 is connected in parallel with the secondary winding to improve the driving capability of the output driving module 1 .

[0064] In one possible implementation, reference Figure 3 and Figure 4 , the number of secondary windings can be two (T1B and T1C);

[0065] The first end of the first secondary winding (T1A) and the second end of the second secondary winding (T1C) are terminals of the same name.

[0066] In an embodiment of the utility model, two secondary windings can be provided, and the like-named ends of the two secondary windings (T1B and T1C) are opposite, so that the switch tube drive signals output by the two output drive modules 1 are complementary, thereby realizing the output of two complementary switch tube drive signals.

[0067] The number of secondary windings is not limited to two, and may be other numbers. The positions of the same-name ends and opposite-name ends of each secondary winding are not limited and may be set according to actual application requirements.

[0068] In one possible implementation, reference Figure 3 , the above circuit may further include: an input module 2;

[0069] The input end of the input module 2 is used to input a differential signal, and the first output end and the second output end of the input module 2 are respectively connected to the two ends of the primary winding (T1A) of the driving transformer T1.

[0070] The specific circuit diagram of input module 2 can be referred to Figure 4 The details will not be described here in detail, as they are conventional technical means in this field.

[0071] Corresponding to the above embodiments, an embodiment of the utility model further provides a power supply, including the switch tube driving circuit provided by any of the above embodiments, and having the advantages of the above switch tube driving circuit, which will not be described in detail here.

[0072] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. 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 invention.

Claims

1. A switch tube driving circuit, characterized in that: include: A driving transformer and at least one output driving module; wherein the driving transformer comprises: a primary winding and at least one secondary winding; each secondary winding corresponds to each output driving module one by one; The primary winding is used to input a differential signal; For any secondary winding, the first end of the secondary winding is connected to the first input end of the output driving module corresponding to the secondary winding, and the second end of the secondary winding is connected to the second input end of the output driving module corresponding to the secondary winding; the first output end and the second output end of the output driving module corresponding to the secondary winding are used to output the switch tube driving signal corresponding to the secondary winding; The output driving module includes: a voltage dividing unit, a switch unit, a first diode, a first voltage stabilizing diode, a first capacitor and an output filtering unit; The first input end of the output driving module is respectively connected to the first end of the switch unit, the first end of the output filter unit and the first output end of the output driving module, and the second input end of the output driving module is respectively connected to the cathode of the first diode and the first end of the voltage dividing unit; The second end of the switch unit is connected to the anode of the first diode, the anode of the first voltage regulator diode and the first end of the first capacitor respectively, and the control end of the switch unit is connected to the second end of the voltage divider unit; The cathode of the first voltage stabilizing diode, the second end of the first capacitor and the second end of the output filtering unit are all connected to the second output end of the output driving module.

2. The switch tube driving circuit according to claim 1, characterized in that: The voltage dividing unit also includes a third end; the third end of the voltage dividing unit is respectively connected to the second end of the switch unit, the anode of the first diode, the anode of the first voltage stabilizing diode and the first end of the first capacitor; the voltage dividing unit includes: a first resistor and a second resistor; The first end of the first resistor is connected to the first end of the voltage dividing unit, and the second end of the first resistor is connected to the first end of the second resistor and the second end of the voltage dividing unit respectively; The second end of the second resistor is connected to the third end of the voltage dividing unit.

3. The switch tube driving circuit according to claim 2, characterized in that: The switch unit comprises: a third resistor and a first switch tube; The first end of the first switch tube is connected to the first end of the switch unit through the third resistor, the second end of the first switch tube is connected to the second end of the switch unit, and the control end of the first switch tube is connected to the control end of the switch unit.

4. The switch tube driving circuit according to claim 3, characterized in that: The first switch tube is NMOS.

5. The switch tube driving circuit according to any one of claims 1 to 4, characterized in that: The output filter unit includes: a second diode, a fourth resistor and a second capacitor; An anode of the second diode is connected to a first end of the output filter unit, and a cathode of the second diode is connected to a second end of the output filter unit via the fourth resistor; The second capacitor is connected in parallel with the fourth resistor.

6. The switch tube driving circuit according to any one of claims 1 to 4, characterized in that: The output driving module further includes: a fifth resistor; The first input terminal of the output driving module is respectively connected to the first terminal of the switch unit, the first terminal of the output filtering unit and the first output terminal of the output driving module through the fifth resistor.

7. The switch tube driving circuit according to any one of claims 1 to 4, characterized in that: The output driving module further includes: a sixth resistor; Two ends of the sixth resistor are connected to the first input end of the output driving module and the second input end of the output driving module respectively.

8. The switch tube driving circuit according to any one of claims 1 to 4, characterized in that: The number of the secondary windings is two; The first end of the first secondary winding and the second end of the second secondary winding are terminals of the same name.

9. A power supply, characterized in that: It comprises the switch tube driving circuit as claimed in any one of claims 1 to 8.

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