Driving circuit and H-bridge circuit

Abstract

The utility model discloses a drive circuit and an H-bridge circuit, the drive circuit is configured with a capacitor C3, a resistor R5, a diode D1, a triode T1 and a resistor R7, a first pole plate of the capacitor C3 is connected with one end of the resistor R5 and is used as a first connecting end of the drive circuit for driving signal access; a second pole plate of the capacitor C3 is connected with a second end of the triode T1 and a cathode of the diode D1, and the other end of the resistor R5 is connected with an anode of the diode D1 and a third end of the triode T1, serves as a second connecting end of the driving circuit and is used for being connected with a control end of the MOS tube; the first end of the triode T1 serves as a third connecting end of the driving circuit and is used for being connected with the power end of the MOS tube. The driving circuit is provided with the capacitor to store energy when the MOS tube is controlled to be in a conduction state and release the stored electric energy when the MOS tube is controlled to be in a turn-off state so as to enable the triode T1 to be conducted, so that the driven MOS tube is quickly turned off.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of drive circuit and H bridge circuit. BACKGROUND

[0002] Insulated gate field effect transistors, for example, metal oxide semiconductor field effect transistors have been used in many power switching applications, for example, DC-DC converters, H-bridge drivers. In typical metal oxide semiconductor field effect transistors, the gate provides on and off control by applying appropriate gate voltage (drive signal).

[0003] Gate voltage (drive signal) is generated by drive circuit, and some existing drive circuits cannot make the driven MOS tube quickly shut down. SUMMARY

[0004] In order to solve the technical problems existing in the prior art, the utility model provides a kind of drive circuit, and the circuit can make the driven MOS tube quickly shut down.

[0005] The drive circuit provided by the utility model has the following two structures:

[0006] The first structure is configured with capacitor C3, resistance R5, diode D1, triode T1 and resistance R7, the first plate of the capacitor C3 is connected with one end of the resistance R5, and is used as the first connection end of the drive circuit, for driving signal access;The second plate of the capacitor C3 is connected with the second end of the triode T1 and the cathode of the diode D1, the other end of the resistance R5 is connected with the anode of the diode D1 and the third end of the triode T1, and is used as the second connection end of the drive circuit, for connecting the control end of MOS tube;The first end of the triode T1 is used as the third connection end of the drive circuit, for connecting the power supply end of MOS tube.

[0007] Further, the drive circuit in the structure is further configured with resistance R6 and resistance R7, the resistance R6 is connected on the second connection end, and the resistance R7 is connected between the second connection end and the third connection end.

[0008] The second structure is configured with:

[0009] The upper bridge driving circuit comprises a capacitor C3, a resistor R5, a diode D1 and a triode T1. The first plate of the capacitor C3 is connected to one end of the resistor R5, and serves as a first connection end of the driving circuit for driving signal input. The second plate of the capacitor C3 is connected to the second end of the triode T1 and the cathode of the diode D1. The other end of the resistor R5 is connected to the anode of the diode D1 and the third end of the triode T1, and serves as a second connection end of the driving circuit for connecting the control end of the upper bridge switching device of the H-bridge. The first end of the triode T1 serves as a third connection end of the driving circuit for connecting the power supply end of the upper bridge switching device of the H-bridge.

[0010] The lower bridge driving circuit comprises a triode T2 and a triode T3, which constitute a push-pull structure for driving the lower bridge switching device of the H-bridge.

[0011] Further, the lower bridge driving circuit further comprises a diode D2, a resistor R8 and a resistor R9. The cathode of the diode D2 is connected to one end of the triode T2 and the triode T3, and the anode is connected to one end of the resistor R9. The other end of the resistor R9 serves as a fourth connection end of the driving circuit for connecting the control end of the lower bridge switching device of the H-bridge. The resistor R8 is connected in parallel across the diode D2.

[0012] Further, the driving circuit is further configured with a driving chip IC1 for generating a driving signal.

[0013] Further, the driving circuit is further configured with an overvoltage protection circuit comprising a MOS tube Q, a triode T4 and a zener diode D3. The first end of the MOS tube Q serves as a fifth connection end of the driving circuit for excitation input. The second end of the MOS tube Q is connected to the first end of the triode T4. The third end of the MOS tube Q serves as a sixth connection end of the driving circuit for connecting the power supply end.

[0014] The third end of the triode T4 is connected to the first end of the MOS tube Q, and the second end is connected to one end of a resistor R11. The other end of the resistor R11 serves as a seventh connection end of the driving circuit for excitation input. The first end of the triode T4 serves as an eighth connection end of the driving circuit for excitation input.

[0015] The cathode of the zener diode D3 is connected to the seventh connection end, and the anode serves as a ninth connection end of the driving circuit for excitation input.

[0016] Further, the overvoltage protection circuit is further configured with:

[0017] a filter capacitor C4;

[0018] a light-emitting diode LED for overvoltage indication;

[0019] a resistor R12, one end of which is connected to the first end of the switching device Q, and the other end of which is connected to the second end of the switching device Q.

[0020] Further, the anti-reverse circuit is configured to connect the excitation of the eighth connection end and the ninth connection end to the anti-reverse circuit.

[0021] The utility model further provides a kind of H bridge circuit, and the circuit is configured with MOS tube Q1~MOS tube Q4 and the drive circuit of the MOS tube Q1~MOS tube Q4 conduction, cutoff, the MOS tube Q1 and the MOS tube Q2 are P-MOS tube, and constitute the upper bridge of H bridge;The MOS tube Q3 and the MOS tube Q4 are N-MOS tube, and constitute the lower bridge of H bridge;The drive circuit is the drive circuit provided in the application.

[0022] Further, the H bridge circuit is further configured with bleeder circuit, including diode D5~D8, the anode and cathode of the diode D5 are connected to the source and drain of the MOS tube Q1 respectively, the anode and cathode of the diode D6 are connected to the source and drain of the MOS tube Q2 respectively, the anode and cathode of the diode D7 are connected to the drain and source of the MOS tube Q3 respectively, the anode and cathode of the diode D8 are connected to the drain and source of the MOS tube Q4 respectively.

[0023] The utility model provides drive circuit configuration capacitor in control MOS tube conduction state energy storage, release the energy stored in control MOS tube off state and make triode T1 conduction, realize the MOS tube of being driven fast off.

[0024] The drive circuit is configured with an overvoltage protection circuit to ensure the stability of the circuit. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained from these drawings without creative labor for those skilled in the art. In the drawings:

[0026] Figure 1 The circuit structure diagram of the first structure of the drive circuit provided by the utility model Figure 1 ;

[0027] Figure 2 The circuit structure diagram of the first structure of the drive circuit provided by the utility model Figure 2 ;

[0028] Figure 3 The second structure of the driving circuit provided by the utility model Figure 1 ;

[0029] Figure 4 The first structure of the H bridge circuit provided by the utility model

[0030] Figure 5 The second structure of the H bridge circuit provided by the utility model

[0031] Figure 6 The third structure of the H bridge circuit provided by the utility model. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0033] As used herein, "comprise", "include", "have", "contain", "with" and the like are open-ended terms, i.e., meaning "including but not limited to".

[0034] Embodiment one

[0035] Please refer to Figure 1 The driving circuit provided by the embodiment is configured with a capacitor C3, a resistor R5, a diode D1 and a triode T1. The first plate of the capacitor C3 is connected to one end of the resistor R5 and serves as a first connection end of the driving circuit for driving signal access. The second plate of the capacitor C3 is connected to the second end of the triode T1 and the cathode of the diode D1. The other end of the resistor R5 is connected to the anode of the diode D1 and the third end of the triode T1 and serves as a second connection end of the driving circuit for connecting the control end of the MOS tube. The first end of the triode T1 serves as a third connection end of the driving circuit for connecting the power supply end of the MOS tube.

[0036] The embodiment takes a P-MOS tube as an example of the driven MOS tube to describe the driving principle of the driving circuit. Please refer to Figure 4, the drive signal is low, after R5 voltage division, to the gate of P-MOS tube Q1 is still low, and the source of P-MOS tube Q1 is connected to the power supply VCC continuously high level, the voltage of power supply VCC makes the voltage difference VGS of the gate and source of P-MOS tube Q1 when the low level drive signal is accessed to be greater than 5V, under this condition, P-MOS tube Q1 is completely turned on. Due to the conduction of P-MOS tube Q1, current flows to the base of triode T1 through diode D1, and the voltage difference between the base and the emitter of triode T1 is insufficient, so triode T1 cannot be turned on, that is, triode T1 is in the off state at this time; at this time, the voltage of the second plate of capacitor C3 is V1. When the drive signal is high, the emitter follower amplifier is formed by diode D1 and triode T1, and the gate voltage of P-MOS tube Q1 flows to the second plate of capacitor C3, at this time, the voltage of the second plate of capacitor C3 is V2; because of the one-way current continuation of diode D1, and the voltage across the capacitor cannot change suddenly, the voltage of the second plate of capacitor C3 rises to (V1+V2), and through this rising voltage, triode T1 is quickly turned on, and the gate level of P-MOS tube Q1 is equal to the source level, that is, VGS=0V, and P-MOS tube Q1 is quickly turned off.

[0037] Example two

[0038] The drive circuit provided in the embodiment is configured with capacitor C3, resistor R5, diode D1, triode T1, resistor R6 and resistor R7, and the connection relationship between each component is as shown in Figure 1 .

[0039] Example three

[0040] The drive circuit provided in the embodiment is based on the drive circuit of example one and example two, and further includes a drive chip IC1 for generating a drive signal, as shown in Figure 2 . The drive chip IC1 is configured as a NE555 drive chip, and resistor R1-resistor R3, capacitor C1 and capacitor C2 are peripheral devices of the drive chip IC1, which provide parameters required for the operation of the drive chip IC1, so as to ensure that the drive chip IC1 can generate a drive signal.

[0041] Example four

[0042] The drive circuit provided in the embodiment is based on the drive circuit of example one and example two, and further includes an overvoltage protection circuit. Please refer to Figure 2 , the overvoltage protection circuit includes MOS tube Q, triode T4 and voltage stabilizing diode D3, the first end of MOS tube Q is used as the fifth connection end of the drive circuit for excitation; the second end of MOS tube Q is connected to the first end of triode T4, and the third end of MOS tube Q is used as the sixth connection end of the drive circuit for connecting the power supply end of the MOS tube.

[0043] The third terminal of the triode T4 is connected to the first terminal of the MOS transistor Q, and the second terminal of the MOS transistor Q is connected to one terminal of the resistor R11, and the other terminal of the resistor R11 is connected to the seventh connection terminal of the driving circuit and is used for excitation connection; the first terminal of the triode T4 is connected to the eighth connection terminal of the driving circuit and is used for excitation connection.

[0044] The cathode of the voltage stabilizing diode D3 is connected to the seventh connection terminal, and the anode is connected to the ninth connection terminal of the driving circuit and is used for excitation connection.

[0045] The described “excitation” refers to the power supply + (such as +5V, +10V, +12V), ground or power supply - (such as -5V, -10V, -12V) required by the circuit, as shown in the figure, VCC is the power supply +, GND is the ground or power supply -, according to the circuit structure configuration. Figure 2 As shown, the MOS transistor Q is a P-MOS transistor, the triode T4 is a PNP, and the excitation connected to the fifth connection terminal and the seventh connection terminal is VCC; the excitation connected to the eighth connection terminal and the ninth connection terminal is GND; if the MOS transistor Q is an N-MOS transistor, the triode T4 is an NPN, and the excitation connected is adjusted accordingly.

[0046] The overvoltage protection principle is that the VCC voltage is less than or equal to the voltage of the voltage stabilizing diode D3, at this time the triode T4 is cut off, Q is turned on, VCC is connected to the power supply terminal of the MOS transistor through the MOS transistor Q, and the MOS transistor can be normally driven. If the VCC voltage is greater than the voltage of the voltage stabilizing diode, the triode T4 is turned on, Q is cut off, and VCC cannot supply power to the MOS transistor, so the MOS transistor cannot be normally driven.

[0047] The overvoltage protection circuit further comprises one, part or all of the following components:

[0048] The filter capacitor C4;

[0049] The light-emitting diode LED is used for overvoltage indication;

[0050] The resistor R12 has one terminal connected to the first terminal of the switching device Q and the other terminal connected to the second terminal of the switching device Q.

[0051] The anti-reverse circuit is connected to the excitation connected to the eighth connection terminal and the ninth connection terminal; the anti-reverse circuit comprises a diode D4, and the connection relationship is as shown in Figure 2 .

[0052] Example five

[0053] Please refer to Figure 3 The driving circuit provided in the embodiment is configured with:

[0054] The upper bridge driving circuit comprises a capacitor C3, a resistor R5, a diode D1 and a triode T1. The first plate of the capacitor C3 is connected to one end of the resistor R5 and serves as a first connecting end of the driving circuit for driving signal input. The second plate of the capacitor C3 is connected to the second end of the triode T1 and the cathode of the diode D1. The other end of the resistor R5 is connected to the anode of the diode D1 and the third end of the triode T1 and serves as a second connecting end of the driving circuit for connecting to the control end of the upper bridge switching device of the H-bridge. The first end of the triode T1 serves as a third connecting end of the driving circuit for connecting to the power supply end of the upper bridge switching device of the H-bridge.

[0055] The lower bridge driving circuit comprises a triode T2 and a triode T3, which constitute a push-pull structure for driving the lower bridge switching device of the H-bridge.

[0056] The driving principle of the upper bridge driving circuit is the same as that of the driving circuit provided in the embodiment, which will not be described here.

[0057] The lower bridge driving circuit is driven by the totem pole circuit and has strong output current capacity. As shown in the figure, when the driving signal input into the lower bridge driving circuit is at high level (about 12V), the triode T2 is turned on, the triode T3 is turned off, and the N-MOS tube Q3 gate receives a high level and is thus turned on. When the driving signal is at low level, the triode T2 is turned off, the triode T3 is turned on, and the N-MOS tube Q3 gate receives a low level and is thus turned off.

[0058] Embodiment six

[0059] The driving circuit provided in the embodiment further comprises a diode D2, a resistor R8 and a resistor R9 on the basis of the driving circuit of the embodiment five. The cathode of the diode D2 is connected to one end of the triode T2 and the triode T3, and the anode is connected to one end of the resistor R9. The other end of the resistor R9 serves as a fourth connecting end of the driving circuit for connecting to the control end of the lower bridge switching device of the H-bridge. The resistor R8 is connected in parallel to the diode D2. The resistor R8 increases the damping on the transmission line to avoid ringing.

[0060] The diode D2 provides a rapid energy discharge circuit for the gate of the N-MOS tube Q3 when it is turned off, which is rapidly consumed through the circuit composed of the diode D2 and the resistor R8.

[0061] Embodiment seven

[0062] The driving circuit provided in the embodiment further comprises a driving chip IC1 for generating a driving signal on the basis of the driving circuits of the embodiment five and the embodiment six, such as Figure 3The driving chip IC1 is configured as a NE555 driving chip, and the resistors R1-R3 and the capacitors C1 and C2 are peripheral devices of the driving chip IC1, which provide parameters required for the driving chip IC1 to work and ensure that the driving chip IC1 can generate a driving signal.

[0063] Embodiment Eight

[0064] The driving circuit provided in the embodiment further comprises an overvoltage protection circuit on the basis of the driving circuits in the embodiments five, six and seven. Figure 3 The overvoltage protection circuit comprises a MOS tube Q, a triode T4 and a stabilizing diode D3, the first end of the MOS tube Q is configured as the fifth connecting end of the driving circuit and is used for excitation connection, the second end of the MOS tube Q is connected to the first end of the triode T4, and the third end of the MOS tube Q is configured as the sixth connecting end of the driving circuit and is used for connecting the power supply end of the H-bridge.

[0065] The third end of the triode T4 is connected to the first end of the MOS tube Q, the second end is connected to one end of the resistor R11, the other end of the resistor R11 is configured as the seventh connecting end of the driving circuit and is used for excitation connection, and the first end of the triode T4 is configured as the eighth connecting end of the driving circuit and is used for excitation connection.

[0066] The cathode of the stabilizing diode D3 is connected to the seventh connecting end, and the anode is configured as the ninth connecting end of the driving circuit and is used for excitation connection.

[0067] The meaning of "excitation" described in the embodiment is the same as that in the embodiment four, and the overvoltage protection principle of the embodiment is similar to that of the embodiment four, which will not be described herein again.

[0068] The overvoltage protection circuit of the embodiment further comprises one, part or all of the following components:

[0069] A filter capacitor C4;

[0070] A light-emitting diode LED used for overvoltage indication;

[0071] A resistor R12, one end of the resistor R12 is connected to the first end of the switching device Q, and the other end is connected to the second end of the switching device Q.

[0072] A reverse prevention circuit, the excitation connected to the eighth connecting end and the ninth connecting end is connected to the reverse prevention circuit, and the reverse prevention circuit comprises a diode D4, and the connection relationship is as shown in Figure 3

[0073] When the driving circuit provided in the utility model is used to construct an H-bridge circuit, the constructed H-bridge circuit is as shown in Figures 4-6 ​As shown, the H bridge is composed of MOS Q1~MOS Q4, MOS Q1~MOS Q4 can be P-MOS or N-MOS, each MOS can be configured with a drive circuit of the utility model for driving respectively, such as Figure 4 、 5 As shown; or MOS Q1 and MOS Q2 are P-MOS, constituting the upper bridge of H bridge, MOS Q3 and MOS Q4 are N-MOS, constituting the lower bridge of H bridge, under this structure, since P-MOS+N-MOS structure is adopted for the upper and lower bridges of H bridge, the structure as shown in Figure 6 Can be realized by occupying only one I / O port of the drive chip IC1; of course, it can be understood that, under the structure that MOS Q1 and MOS Q2 are P-MOS, constituting the upper bridge of H bridge, MOS Q3 and MOS Q4 are N-MOS, constituting the lower bridge of H bridge, each MOS can also be configured with a drive circuit of the utility model for driving respectively.

[0074] The H bridge circuit under the control of the drive circuit can realize the control of the motor M positive and negative rotation.

[0075] The H bridge circuit is also configured with a bleeder circuit, please refer to Figure 6 The bleeder circuit includes diodes D5~D8, the anode and cathode of diode D5 are connected to the source and drain of MOS Q1 respectively, the anode and cathode of diode D6 are connected to the source and drain of MOS Q2 respectively, the anode and cathode of diode D7 are connected to the drain and source of MOS Q3 respectively, and the anode and cathode of diode D8 are connected to the drain and source of MOS Q4 respectively.

[0076] The drain of MOS Q1~MOS Q4 is connected to the load (such as motor) as the output of H bridge, when the load is inductive load, the bleeder circuit is connected to the load, constituting the bleeder circuit of the load, effectively preventing the instantaneous pulse current / voltage generated by the inductive load at the moment of starting and stopping from damaging the MOS in the H bridge circuit.

[0077] The above embodiments are only used to illustrate the technical solutions of the present application and not to limit, although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the present application, which should be covered in the scope of the claims of the present application. The technical, shape and structure parts not described in detail in the present application are all known technologies.

Claims

1. A drive circuit characterized by comprising: The driving circuit is configured with a capacitor C3, a resistor R5, a diode D1, a triode T1 and a resistor R7, a first plate of the capacitor C3 is connected with one end of the resistor R5, and serves as a first connecting end of the driving circuit for driving signal access; a second plate of the capacitor C3 is connected with a second end of the triode T1 and a cathode of the diode D1, the other end of the resistor R5 is connected with an anode of the diode D1 and a third end of the triode T1, and serves as a second connecting end of the driving circuit for connecting a control end of the MOS tube; a first end of the triode T1 serves as a third connecting end of the driving circuit for connecting a power supply end of the MOS tube.

2. The drive circuit according to claim 1, characterized in that, The driving circuit is further configured with a resistor R6 and a resistor R7, the resistor R6 is connected to the second connecting end, and the resistor R7 is connected between the second connecting end and the third connecting end.

3. A drive circuit, characterized by The driving circuit is configured with: The upper bridge driving circuit comprises a capacitor C3, a resistor R5, a diode D1 and a triode T1, a first plate of the capacitor C3 is connected with one end of the resistor R5, and serves as a first connecting end of the driving circuit for driving signal access; a second plate of the capacitor C3 is connected with a second end of the triode T1 and a cathode of the diode D1, the other end of the resistor R5 is connected with an anode of the diode D1 and a third end of the triode T1, and serves as a second connecting end of the driving circuit for connecting a control end of the H-bridge upper bridge switching device; a first end of the triode T1 serves as a third connecting end of the driving circuit for connecting a power supply end of the H-bridge upper bridge switching device; The lower bridge driving circuit comprises a triode T2 and a triode T3, the triode T2 and the triode T3 constitute a push-pull structure for driving the H-bridge lower bridge switching device.

4. The drive circuit according to claim 3, characterized in that, The lower bridge driving circuit further comprises a diode D2, a resistor R8 and a resistor R9, a cathode of the diode D2 is connected with one end of the triode T2 and the triode T3, an anode of the diode D2 is connected with one end of the resistor R9, the other end of the resistor R9 serves as a fourth connecting end of the driving circuit for connecting a control end of the H-bridge lower bridge switching device; the resistor R8 is connected in parallel with the diode D2.

5. The drive circuit according to any one of claims 1 to 4, characterized by The driving circuit is further configured with a driving chip IC1 for generating a driving signal.

6. The drive circuit according to any one of claims 1 to 4, characterized by The driving circuit is further configured with an overvoltage protection circuit comprising a MOS tube Q, a triode T4 and a voltage stabilizing diode D3, a first end of the MOS tube Q serves as a fifth connecting end of the driving circuit for excitation access; a second end of the MOS tube Q is connected with a first end of the triode T4, a third end of the MOS tube Q serves as a sixth connecting end of the driving circuit for connecting a power supply end; a third end of the triode T4 is connected with the first end of the MOS tube Q, a second end of the triode T4 is connected with one end of a resistor R11, the other end of the resistor R11 serves as a seventh connecting end of the driving circuit for excitation access; a first end of the triode T4 serves as an eighth connecting end of the driving circuit for excitation access; a cathode of the voltage stabilizing diode D3 is connected with the seventh connecting end, and an anode of the voltage stabilizing diode D3 serves as a ninth connecting end of the driving circuit for excitation access.

7. The drive circuit according to claim 6, characterized in that, The overvoltage protection circuit is further configured with: Filtering capacitor C4; Light emitting diode LED for overvoltage indication; Resistor R12, one end of which is connected to the first end of the switching device Q, and the other end of which is connected to the second end of the switching device Q.

8. The drive circuit of claim 6, wherein, Further configured with a reverse prevention circuit, the excitation of the eighth connection end and the ninth connection end is connected through the reverse prevention circuit.

9. An H-bridge circuit, characterized by The circuit is configured with MOS tubes Q1, Q2, Q3, Q4 and a driving circuit for controlling the conduction and cutoff of the MOS tubes Q1-Q4, the MOS tubes Q1 and Q2 are P-MOS tubes, constituting the upper bridge of the H-bridge; the MOS tubes Q3 and Q4 are N-MOS tubes, constituting the lower bridge of the H-bridge; and the driving circuit is the driving circuit of any one of claims 1-8.

10. The H-bridge circuit of claim 9, wherein, The circuit is further configured with a bleeder circuit, including diodes D5-D8, the anode and cathode of the diode D5 are connected to the source and drain of the MOS tube Q1 respectively, the anode and cathode of the diode D6 are connected to the source and drain of the MOS tube Q2 respectively, the anode and cathode of the diode D7 are connected to the drain and source of the MOS tube Q3 respectively, and the anode and cathode of the diode D8 are connected to the drain and source of the MOS tube Q4 respectively.

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