A driving circuit, a driving system and a driving method

Abstract

This invention relates to the field of power management circuit technology, and particularly to a driving circuit, driving system, and driving method. The driving circuit includes: multiple cascaded level shifting modules, clamping modules, and driving modules; each clamping module includes multiple clamping sub-modules corresponding to a level shifting module; each clamping sub-module provides a corresponding clamping voltage to each level shifting module; each level shifting module converts the control signal received at its input terminal into a higher-level control signal, thereby converting the first and second control signals into progressively increasing control signals via each level shifting module; the driving module outputs a driving signal to an external power switch based on the control signal output from the last level shifting module. This driving circuit is applicable to power management circuits with higher operating voltages.

Description

Technical Field

[0001] The present invention relates to the field of power management circuit technology, and in particular to a driving circuit, driving system and driving method. Background Technology

[0002] The main function of the level shifting circuit in the drive circuit is to convert the low-voltage control signal into a high-voltage drive signal, thereby controlling the opening and closing of the external power switch (MOSFET).

[0003] In traditional driver circuits, the high-side power supply port is connected to an external power supply. To ensure the normal operation of the driver circuit, the operating voltage of the power supply input cannot exceed the drain-source withstand voltage of all driver transistors in the driver circuit. This makes traditional driver circuits unsuitable for power management circuits with higher operating voltages.

[0004] Therefore, a new driving circuit is urgently needed. Summary of the Invention

[0005] To address the problem that traditional drive circuits cannot be applied to power management circuits with higher operating voltages, embodiments of the present invention provide a drive circuit, a drive system, and a drive method.

[0006] In a first aspect, embodiments of the present invention provide a driving circuit, comprising: a plurality of level shifting modules, clamping modules and driving modules cascaded in sequence; the clamping module includes a plurality of clamping sub-modules corresponding one-to-one with the level shifting modules;

[0007] The output terminal of each clamping submodule is connected to the corresponding level shifting module, and each clamping submodule is used to provide a corresponding clamping voltage to each level shifting module.

[0008] Each level shift module has two input terminals connected to the two output terminals of the previous level shift module. The two input terminals of the first level shift module are connected to the first control signal and the second control signal, respectively. The two output terminals of the last level shift module are connected to the two input terminals of the drive module. Each level shift module is used to convert the control signal received at the input terminal of the current level shift module into a higher level control signal, so that the first control signal and the second control signal are converted into control signals with progressively increasing levels through each level shift module. The high-side terminal of the last level shift module is connected to the operating voltage provided by an external power supply, and the voltage of the high-side terminal of each level shift module increases progressively.

[0009] The low-side terminal of the drive module is connected to the clamping sub-module of the last stage. The two input terminals of the drive module are respectively connected to the two output terminals of the level shifting module of the last stage. The output terminal of the drive module is connected to an external power switch. The drive module is used to output a drive signal to the external power switch according to the control signal output by the level shifting module of the last stage.

[0010] Secondly, embodiments of the present invention also provide a driving system, including: a power supply, a power switch, and a driving circuit as described in any embodiment of this specification;

[0011] The input terminal of the power switch is connected to the drive circuit; the power supply is connected to both the drive circuit and the power switch, and the power supply is used to provide operating voltage to the drive circuit and the power switch so that the drive circuit outputs a drive signal to the power switch to control the operating state of the power switch.

[0012] Thirdly, embodiments of the present invention also provide a driving method based on the driving circuit described in any embodiment of this specification, comprising:

[0013] Each clamping submodule in the clamping module provides a corresponding clamping voltage to the corresponding level shifting module.

[0014] Based on the clamping voltage of each clamping submodule and the operating voltage provided by the external power supply, a multi-level level shifting module is used to sequentially convert the first and second control signals received by the first-level level shifting module into control signals with progressively increasing levels. The high-side terminal of the last-level level shifting module is connected to the operating voltage, and the voltage of the high-side terminal of each level shifting module increases progressively. Furthermore, the voltage of the high-side terminal of each level shifting module other than the last level shifting module is lower than the operating voltage.

[0015] The drive module outputs a drive signal to an external power switch based on the control signal output by the last-stage level shift module, in order to control the working state of the power switch.

[0016] This invention provides a driving circuit, driving system, and driving method. Each clamping submodule in a clamping module provides a corresponding clamping voltage to a corresponding level shifting module. Then, based on the clamping voltage of each clamping submodule and the operating voltage provided by an external power supply, a multi-stage level shifting module sequentially converts the first and second control signals received by the first-stage level shifting module into control signals with progressively increasing levels. The high-side terminal of the last-stage level shifting module is connected to the operating voltage provided by the power supply. The voltage at the high-side terminal of each level shifting module increases progressively, and the voltage at the high-side terminal of each level shifting module except the last one is lower than the operating voltage provided by the power supply. Finally, the driving module outputs a driving signal to an external power switch based on the control signal output by the last-stage level shifting module to control the operating state of the power switch. This increases the input operating voltage, further enabling the driving circuit of this solution to be applicable to power management circuits with higher operating voltages. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a conventional driving circuit diagram provided in an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of a driving circuit structure provided in an embodiment of the present invention;

[0020] Figure 3 This is a circuit diagram of a level shifting module provided in an embodiment of the present invention;

[0021] Figure 4 This is a driving circuit diagram provided in one embodiment of the present invention;

[0022] Figure 5 This is a circuit diagram of another level shifting module provided in one embodiment of the present invention;

[0023] Figure 6 This is another driving circuit diagram provided in one embodiment of the present invention;

[0024] Figure 7 This is a flowchart of a driving method provided in an embodiment of the present invention;

[0025] Among them, 11 and 21 are power switches; 12 and 22 are drive modules; 13 and 231-23N are level shifting modules; 14 and 24 are clamping modules; and 241-24N are clamping sub-modules. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0027] As mentioned earlier, the high-side power supply port in a traditional drive circuit is connected to an external power supply. In order to ensure the normal operation of the drive circuit, the operating voltage of the power supply input cannot be greater than the drain-source withstand voltage of all drive transistors in the drive circuit. This makes the traditional drive circuit unsuitable for power management circuits with higher operating voltages.

[0028] like Figure 1 The diagram shows a traditional PMOS power switch drive circuit. During operation, the voltage between the drain and source of MOSFETs M6, M7, M8, M9, M10, M11, M13, and M14 is at most equal to the operating voltage VIN. To ensure normal operation of the drive circuit, the high-side operating voltage VIN cannot exceed the withstand voltage between the drain and source of M6, M7, M8, M9, M10, M11, M13, and M14. Therefore, traditional drive circuits are not suitable for power management circuits with higher operating voltages.

[0029] To solve the aforementioned technical problems, the inventors could consider cascading multiple level shifting modules sequentially and configuring a corresponding clamping submodule for each level shifting module. The last level shifting module would be connected to the operating voltage VIN provided by an external power supply. In this way, except for the last level shifting module, the voltage at the high-side of each level shifting module would be lower than the operating voltage VIN, and the voltage would increase progressively. This would ensure that the drain-source voltage of the MOS transistor in each level shifting module does not exceed the withstand voltage, and would also increase the applicable operating voltage VIN of the drive circuit. Furthermore, it would allow the drive circuit to be used with power management circuits with higher operating voltages.

[0030] The following describes the specific implementation of the above concept.

[0031] Please refer to Figure 2This invention provides a driving circuit, which includes: a plurality of level shifting modules, a clamping module 24 and a driving module 22 connected in sequence; the clamping module 24 includes a plurality of clamping sub-modules that correspond one-to-one with the level shifting modules;

[0032] The output terminal of each clamping submodule is connected to the corresponding level shifting module, and each clamping submodule is used to provide a corresponding clamping voltage to each level shifting module.

[0033] Each level shift module has two input terminals connected to the two output terminals of the previous level shift module. The two input terminals of the first level shift module are connected to the first control signal and the second control signal, respectively. The two output terminals of the last level shift module are connected to the two input terminals of the drive module 22, respectively. Each level shift module is used to convert the control signal received at the input terminal of the current level shift module into a higher level control signal, so that the first control signal and the second control signal are converted into control signals with progressively increasing levels through each level shift module. The high-side terminal of the last level shift module is connected to the operating voltage provided by an external power supply, and the voltage of the high-side terminal of each level shift module increases progressively.

[0034] The low-side terminal of the drive module 22 is connected to the clamping sub-module of the last stage. The two input terminals of the drive module 22 are respectively connected to the two output terminals of the level shifting module of the last stage. The output terminal of the drive module 22 is connected to the external power switch 21. The drive module 22 is used to output a drive signal to the external power switch 21 according to the control signal output by the level shifting module of the last stage.

[0035] In this embodiment of the invention, each clamping submodule in the clamping module 24 provides a corresponding clamping voltage to the corresponding level shifting module. Then, based on the clamping voltage of each clamping submodule and the operating voltage provided by the external power supply, a multi-stage level shifting module sequentially converts the first and second control signals received by the first-stage level shifting module into control signals with progressively increasing levels. The high-side terminal of the last-stage level shifting module is connected to the operating voltage provided by the power supply, and the voltage at the high-side terminal of each level shifting module increases progressively. Furthermore, the voltage at the high-side terminal of each level shifting module except the last-stage level shifting module is lower than the operating voltage provided by the power supply. Finally, the driving module 22 outputs a driving signal to the external power switch 21 based on the control signal output by the last-stage level shifting module to control the operating state of the power switch 21. Therefore, this solution can increase the input operating voltage, further enabling the driving circuit of this solution to be applicable to power management circuits with higher operating voltages.

[0036] The following is based on Figure 2 The schematic diagram of the driving circuit shown is used for illustration.

[0037] refer to Figure 3 In some implementations, the level shifting module includes an upper driving MOSFET and a lower driving MOSFET, and the upper driving MOSFET and the lower driving MOSFET are of different types.

[0038] When the clamping submodule includes a first clamping branch for providing a first clamping voltage to the upper driving MOSFET, both the upper driving MOSFET and the lower driving MOSFET in the level shifting module are high-voltage MOSFETs.

[0039] For example, when the power switch is a PMOS transistor, the upper drive transistors M9 and M8 are both high-voltage PMOS transistors, while the lower drive transistors M13 and M14 are both high-voltage NMOS transistors. It should be noted that the types of upper and lower drive MOS transistors differ: if both upper drive MOS transistors are PMOS transistors, then the lower drive transistor is an NMOS transistor, and vice versa. The specific type depends on the circuit design.

[0040] In some implementations, when the power switch is a PMOS transistor, the upper driving MOS transistor in the level shifting module is a high-voltage PMOS transistor, and the lower driving MOS transistor is a high-voltage NMOS transistor.

[0041] The level shifting module includes: PMOS transistor M4, NMOS transistor M5, upper drive transistor M8, upper drive transistor M9, lower drive transistor M13, and lower drive transistor M14;

[0042] The gate of PMOS transistor M4 is connected to the drain of NMOS transistor M5 and the source of the upper driving transistor M9. The source is connected to the high side of the level shifting module, and the drain is connected to the gate of NMOS transistor M5 and the source of the upper driving transistor M8.

[0043] The source of NMOS transistor M5 is connected to the high side of the level shifting module;

[0044] The upper driving transistor M8 has its gate connected to the first clamping voltage of the corresponding clamping submodule, its drain connected to the drain of the lower driving transistor M13, and its source used as the first output terminal of the level shifting module.

[0045] The gate of the upper driving transistor M9 is connected to the first clamping voltage of the corresponding clamping submodule, the drain is connected to the drain of the lower driving transistor M14, and the source serves as the second output terminal of the level shifting module.

[0046] The lower drive transistor M13 has its gate connected to the first input terminal of the level shifting module, and its source connected to the low-side terminal of the level shifting module.

[0047] The lower drive transistor M14 has its gate as the second input terminal of the level shifting module and its source connected to the low side of the level shifting module.

[0048] In this embodiment, since the upper and lower driving transistors are of different types, the clamping voltages required for PMOS and NMOS transistors are different. When the clamping submodule only includes a first clamping branch for providing a first clamping voltage to the upper driving MOS transistor, the drain-source voltages of both the upper and lower driving transistors in the level shifting module are at risk of exceeding their withstand voltage. Therefore, both the upper and lower driving transistors in the level shifting module are high-voltage MOS transistors.

[0049] For example, in this embodiment, the power switch is a PMOS transistor, so the upper driving MOS transistor in the level shifting module is a high-voltage PMOS transistor, and the lower driving MOS transistor is a high-voltage NMOS transistor.

[0050] In some implementations, the first clamping branch includes: a Zener diode D1 and a resistor R1;

[0051] Zener diode D1, with its cathode connected to the high side of the level shifting module and its anode connected to one end of resistor R1, serves as the output terminal of the first clamping branch, used to output the first clamping voltage;

[0052] Resistor R1, the other end of which is connected to the low side of the level shifting module.

[0053] In this embodiment of the invention, the driving module 22 may include: PMOS transistor M2, PMOS transistor M3, NMOS transistor M6 and NMOS transistor M7;

[0054] The gate of PMOS transistor M2 is connected to the gate of NMOS transistor M6, the drain is connected to the drain of NMOS transistor M6, and the source is connected to the high side of the last stage level shifting module. The gate of PMOS transistor M2 serves as an input terminal of the driving module and is connected to the second output terminal of the last stage level shifting module. The drain of PMOS transistor M2 serves as an output terminal of the driving module and is connected to the power switch.

[0055] The gate of PMOS transistor M3 is connected to the gate of NMOS transistor M7, the drain is connected to the drain of NMOS transistor M7, and the source is connected to the high side of the last stage level shifting module. The gate of PMOS transistor M3 serves as another input terminal of the drive module and is connected to the first output terminal of the last stage level shifting module. The drain of PMOS transistor M3 serves as another output terminal of the drive module and is connected to the power switch.

[0056] The source of NMOS transistor M6 is connected to the first clamping voltage of the last stage clamping submodule;

[0057] The source of NMOS transistor M7 is connected to the first clamping voltage of the last stage clamping submodule.

[0058] In embodiments of the present invention, such as Figure 4 As shown, there are two. Figure 3 The diagram shows the driving circuit diagram when the level shifting modules are cascaded.

[0059] As can be seen, the high-side terminal of the first stage is connected to the second-stage clamping submodule 242, and the output terminal of the first-stage clamping submodule 241 serves as the low-side terminal of the second-stage level shifting module 232. The first input terminal of the first-stage level shifting module 231 is connected to the first control signal IN-, and the second input terminal is connected to the second control signal IN+. The first control signal IN- and the second control signal IN+ are shifted to a high level by the level shifting module 231, and then connected to the second input terminal and the first input terminal of the second-stage level shifting module 232 through the first and second output terminals of the level shifting module 231, respectively. The second-stage level shifting module 232 converts the control signal to a higher level through level shifting, and then transmits it to the drive module 22 through the second and first output terminals of the level shifting module 232. The drive module 22 outputs a drive signal to the external power switch 21 according to the control signal output by the second-stage level shifting module 232, thereby controlling the power switch 21 to turn on and off. In this circuit, the high-side terminal of the level shift module 232 is connected to the operating voltage VIN provided by the external power supply. Therefore, the voltage at the high-side terminal of the level shift module 231 will be lower than the operating voltage VIN. This ensures that the drain-source voltage of the MOS transistors of the level shift modules 231 and 232 will not exceed the withstand voltage, and also increases the applicable operating voltage VIN of the drive circuit. Furthermore, it allows the drive circuit to be used with power management circuits with higher operating voltages.

[0060] However, Figure 3 and Figure 4 In the driving circuit shown, both the upper and lower driving transistors of the level shift module 231 are high-voltage MOSFETs. Typically, in manufacturing processes, high-voltage MOSFETs require additional masking and manufacturing steps compared to low-voltage MOSFETs, increasing production costs. Furthermore, high-voltage MOSFETs generally occupy a larger chip area and have larger parasitic capacitance, thereby increasing the delay time of the level shift module and reducing the speed of the driving circuit.

[0061] Therefore, in some implementations, reference Figure 5 and Figure 6 When the clamping submodule includes a first clamping branch for providing a first clamping voltage to the upper driving MOSFET and a second clamping branch for providing a second clamping voltage to the lower driving MOSFET, both the upper driving MOSFET and the lower driving MOSFET in the level shifting module are low-voltage MOSFETs.

[0062] Specifically, when the power switch is a PMOS transistor, the upper drive MOS transistor in the level shifting module is a low-voltage PMOS transistor, and the lower drive MOS transistor is a low-voltage NMOS transistor;

[0063] The level shifting module includes: PMOS transistor M4, NMOS transistor M5, upper drive transistor M8, upper drive transistor M9, lower drive transistor M11, lower drive transistor M12, lower drive transistor M13 and lower drive transistor M14;

[0064] The gate of PMOS transistor M4 is connected to the drain of NMOS transistor M5 and the source of the upper driving transistor M9. The source is connected to the high side of the level shifting module, and the drain is connected to the gate of NMOS transistor M5 and the source of the upper driving transistor M8.

[0065] The source of NMOS transistor M5 is connected to the high side of the level shifting module;

[0066] The upper driving transistor M8 has its gate connected to the first clamping voltage of the corresponding clamping submodule, its drain connected to the drain of the lower driving transistor M11, and its source used as the first output terminal of the level shifting module.

[0067] The gate of the upper driving transistor M9 is connected to the first clamping voltage of the corresponding clamping submodule, the drain is connected to the drain of the lower driving transistor M12, and the source serves as the second output terminal of the level shifting module.

[0068] The lower drive transistor M11 has its gate connected to the second clamping voltage of the corresponding clamping submodule, and its source connected to the drain of the lower drive transistor M13. The lower drive transistor M11 is used to control the gate-source voltage of the lower drive transistor M13 according to the second clamping voltage.

[0069] The lower drive transistor M12 has its gate connected to the second clamping voltage of the corresponding clamping submodule, and its source connected to the drain of the lower drive transistor M14. The lower drive transistor M12 is used to control the gate-source voltage of the lower drive transistor M14 according to the second clamping voltage.

[0070] The lower drive transistor M13 has its gate connected to the first input terminal of the level shifting module, and its source connected to the low-side terminal of the level shifting module.

[0071] The lower drive transistor M14 has its gate as the second input terminal of the level shifting module and its source connected to the low side of the level shifting module.

[0072] In some implementations, the first clamping branch may include: a Zener diode D1 and a resistor R1;

[0073] Zener diode D1, with its cathode connected to the high side of the level shifting module and its anode connected to one end of resistor R1, serves as the output terminal of the first clamping branch, used to output the first clamping voltage;

[0074] Resistor R1, the other end of which is connected to the low side of the level shifting module;

[0075] The second clamping branch may include: resistor R2 and Zener diode D2;

[0076] Resistor R2 is connected at one end to the high side of the level shifting module and at the other end to the cathode of Zener diode D2.

[0077] Zener diode D2 has its anode connected to the low-side of the level shifting module. The anode serves as the output terminal of the second clamping branch, used to output the second clamping voltage.

[0078] In this embodiment, as Figure 5 As shown, the first clamping branch provides a first clamping voltage to the upper driving transistors M8 and M9 of the level shifting module to ensure that the gate-source voltages of M8 and M9 do not exceed the first clamping voltage of the Zener diode D1; the second clamping branch provides a second clamping voltage to the lower driving transistors M11, M12, M13, and M14 of the level shifting module to ensure that the gate-source voltages of M11, M12, M13, and M14 do not exceed the second clamping voltage of the Zener diode D2. The lower driving transistors M11 and M12 are used to control the gate-source voltages of the lower driving transistors M13 and M14 according to the first and second clamping voltages, respectively.

[0079] like Figure 5 The driving circuit shown in the diagram operates in two ways:

[0080] When the first control signal IN- is low (VLO) and the second control signal IN+ is high (VLO+5V): MOSFETs M14 and M12 are on, M9 and M4 are off, M13 and M11 are off, M8 is on, and M5 is off; MOSFETs M3 and M7 are off, M2 and M6 are off. OUT+ is high (VHI) and OUT- is low (VHI-5V).

[0081] When the first control signal IN- is high (VLO+5V) and the second control signal IN+ is low (VLO): MOSFETs M14 and M12 are off, M9 and M4 are on, M13 and M11 are on, M8 is off, and M5 is on; MOSFETs M3, M7, M2, and M6 are on. OUT+ is low (VHI-5V), and OUT- is high.

[0082] By alternating high and low levels of the complementary first control signal IN- and second control signal IN+, the power switch 21 can be controlled to turn on and off.

[0083] In addition, the highest voltage of the second control signal IN+ does not exceed the gate-source breakdown voltage Vgs14(max) of MOSFET M14, and the highest voltage of the first control signal IN- does not exceed the gate-source breakdown voltage Vgs13(max) of MOSFET M13. For ease of description, it is assumed that the turn-on voltage of all MOSFETs is Vth, and the clamping voltage VD of all regulated sources is 5V.

[0084] Therefore, during operation, the maximum value of the gate-source voltage of all NMOS transistors is Vgsn(max) = max(VD-Vth, second control signal IN+, first control signal IN-); the maximum value of the drain-source voltage of all NMOS transistors is Vdsn(max) = max(VD, VHI-VD+Vth).

[0085] For all PMOS transistors, the maximum gate-source voltage Vgsp(max) = VD - Vth; for all PMOS transistors, the maximum drain-source voltage Vdsp(max) = max(VD, VHI - VD + Vth - VLO).

[0086] If the clamping voltages of the regulated power supply are set to VD≤5V, VHI-VD+Vth≤5V, and VHI-VD+Vth-VLO≤5V, then Figure 5 All MOSFETs in the level shifting module shown can be low-voltage 5V MOSFETs.

[0087] From the above formula, we know that VHI-VLO≤5V+VD-Vth≤2*5V-Vth, therefore, using Figure 5 The level shifting module shown can achieve a level shift from 0 to 5V to 5V-VTH to 2*5V-Vth using only a 5V low-voltage MOSFET.

[0088] therefore, Figure 5 The level shifting module shown can achieve a level shift from 0 to 5V to 5V-VTH to 2*5V-Vth when using a 5V low-voltage MOSFET. Compared to... Figure 1 The level shifting module shown improves the level shifting capability of the control signal, which can further enhance the driving capability of the drive circuit.

[0089] In embodiments of the present invention, such as Figure 6 As shown, there are two. Figure 5 The diagram shows the driving circuit diagram when the level shifting modules are cascaded.

[0090] As can be seen, the high-side terminal of the first stage is connected to the first clamping branch and the second clamping branch of the second-stage clamping submodule 242, respectively. The output terminal of the first clamping branch of the first-stage clamping submodule 241 serves as the low-side terminal of the second-stage level shifting module 232. The first input terminal of the first-stage level shifting module 231 is connected to the first control signal IN-, and the second input terminal is connected to the second control signal IN+. The first control signal IN- and the second control signal IN+ are shifted to a high level by the level shifting module 231, and then connected to the second input terminal and the first input terminal of the second-stage level shifting module 232 through the first output terminal and the second output terminal of the level shifting module 231, respectively. The second-stage level shifting module 232 converts the control signal to a higher level through level shifting, and then transmits it to the drive module 22 through the second output terminal and the first output terminal of the level shifting module 232. The drive module 22 outputs a drive signal to the external power switch 21 according to the control signal output by the second-stage level shifting module 232 to control the power switch 21 to turn on and off. The output of the second clamping branch of the second-stage clamping submodule 242 is connected to the low-side terminal of the drive module 22. Therefore, Figure 6 The driving circuit shown, through the cascading of level shift modules, can achieve a level shift from 0 to 5V to 5V*2-2*VTH to 5V*(2+1)-2*Vth using only 5V low-voltage MOSFETs. This not only improves the driving capability and operating voltage VIN, but also avoids the use of high-voltage MOSFETs, thereby reducing processing layers, lowering production costs, reducing the delay time of the level shift modules and driving modules, and increasing the speed of the driving circuit.

[0091] It should be noted that there can be multiple level shift modules, not just two; the specific number can be determined based on the operating voltage of the power switch 21. Therefore, this embodiment, through a cascaded method of level shift modules, can achieve a level shift from 0 to 5V to 5N-N*VTH to 5(N+1)-N*Vth) using only 5V low-voltage MOSFETs. This not only applies to power switches 21 with different operating voltages VIN, but also improves the level shift and drive capabilities of the drive circuit. Furthermore, by avoiding the use of high-voltage MOSFETs, it reduces processing layers, lowers production costs, reduces the delay time of the level shift and drive modules, and increases the speed of the drive circuit.

[0092] This embodiment also provides a drive system, including: a power supply, a power switch, and a drive circuit as described in any embodiment of the specification;

[0093] The input terminal of the power switch is connected to the drive circuit; the power supply is connected to both the drive circuit and the power switch. The power supply provides operating voltage to the drive circuit and the power switch so that the drive circuit outputs a drive signal to the power switch to control the operating state of the power switch.

[0094] like Figure 7 As shown, this embodiment also provides a driving method based on the driving circuit described in any embodiment of the specification, including:

[0095] Step 700: Use each clamping submodule in the clamping module to provide the corresponding clamping voltage to the corresponding level shifting module;

[0096] Step 702: Based on the clamping voltage of each clamping submodule and the operating voltage provided by the external power supply, the first control signal and the second control signal received by the first level level shifting module are sequentially converted into control signals with progressively increasing levels using a multi-level level shifting module; wherein, the high-side terminal of the last level level shifting module is connected to the operating voltage, the voltage of the high-side terminal of each level level shifting module increases progressively, and the voltage of the high-side terminal of each level level shifting module other than the last level level shifting module is lower than the operating voltage;

[0097] Step 704: The drive module outputs a drive signal to the external power switch based on the control signal output by the last level shift module, so as to control the working state of the power switch.

[0098] Since the embodiments of the method of the present invention and the embodiments of the driving circuit of the present invention are based on the same concept, the specific details can be found in the description of the embodiments of the driving circuit of the present invention, and will not be repeated here.

[0099] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A driving circuit, characterized in that, include: Multiple level shifting modules, clamping modules, and driving modules are cascaded in sequence; The clamping module includes multiple clamping sub-modules that correspond one-to-one with the level shifting module; The output terminal of each clamping submodule is connected to the corresponding level shifting module, and each clamping submodule is used to provide a corresponding clamping voltage to each level shifting module. Each level shift module has two input terminals connected to the two output terminals of the previous level shift module. The two input terminals of the first level shift module are connected to the first control signal and the second control signal, respectively. The two output terminals of the last level shift module are connected to the two input terminals of the drive module. Each level shift module is used to convert the control signal received at the input terminal of the current level shift module into a higher level control signal, so that the first control signal and the second control signal are converted into control signals with progressively increasing levels through each level shift module. The high-side terminal of the last level shift module is connected to the operating voltage provided by an external power supply, and the voltage of the high-side terminal of each level shift module increases progressively. The low-side terminal of the drive module is connected to the clamping sub-module of the last stage. The two input terminals of the drive module are respectively connected to the two output terminals of the level shifting module of the last stage. The output terminal of the drive module is connected to an external power switch. The drive module is used to output a drive signal to the external power switch according to the control signal output by the level shifting module of the last stage.

2. The driving circuit according to claim 1, characterized in that, The level shifting module includes an upper driving MOSFET and a lower driving MOSFET, and the upper driving MOSFET and the lower driving MOSFET are of different types; When the clamping submodule includes a first clamping branch for providing a first clamping voltage to the upper driving MOS transistor, both the upper driving MOS transistor and the lower driving MOS transistor in the level shifting module are high-voltage MOS transistors.

3. The driving circuit according to claim 2, characterized in that, When the power switch is a PMOS transistor, the upper driving MOS transistor in the level shifting module is a high-voltage PMOS transistor, and the lower driving MOS transistor is a high-voltage NMOS transistor; The level shifting module includes: PMOS transistor M4, NMOS transistor M5, upper drive transistor M8, upper drive transistor M9, lower drive transistor M13, and lower drive transistor M14; The gate of the PMOS transistor M4 is connected to the connection line between the drain of the NMOS transistor M5 and the source of the upper driving transistor M9, the source is connected to the high side of the level shifting module, and the drain is connected to the connection line between the gate of the NMOS transistor M5 and the source of the upper driving transistor M8. The source of the NMOS transistor M5 is connected to the high side of the level shifting module; The upper driving transistor M8 has its gate connected to the first clamping voltage of the corresponding clamping submodule, its drain connected to the drain of the lower driving transistor M13, and its source serving as the first output terminal of the level shifting module. The upper driving transistor M9 has its gate connected to the first clamping voltage of the corresponding clamping submodule, its drain connected to the drain of the lower driving transistor M14, and its source serving as the second output terminal of the level shifting module. The gate of the lower driving transistor M13 is the first input terminal of the level shifting module, and the source is connected to the low side of the level shifting module. The lower driving transistor M14 has its gate as the second input terminal of the level shifting module and its source connected to the low-side terminal of the level shifting module.

4. The driving circuit according to claim 2, characterized in that, The first clamping branch includes: a Zener diode D1 and a resistor R1; The Zener diode D1 has its cathode connected to the high side of the level shifting module and its anode connected to one end of the resistor R1. The anode serves as the output terminal of the first clamping branch, used to output the first clamping voltage. The other end of the resistor R1 is connected to the low-side terminal of the level shifting module.

5. The driving circuit according to claim 2, characterized in that, When the clamping submodule includes a first clamping branch for providing a first clamping voltage to the upper driving MOSFET and a second clamping branch for providing a second clamping voltage to the lower driving MOSFET, both the upper driving MOSFET and the lower driving MOSFET in the level shifting module are low-voltage MOSFETs.

6. The driving circuit according to claim 5, characterized in that, When the power switch is a PMOS transistor, the upper driving MOS transistor in the level shifting module is a low-voltage PMOS transistor, and the lower driving MOS transistor is a low-voltage NMOS transistor; The level shifting module includes: PMOS transistor M4, NMOS transistor M5, upper drive transistor M8, upper drive transistor M9, lower drive transistor M11, lower drive transistor M12, lower drive transistor M13 and lower drive transistor M14. The gate of the PMOS transistor M4 is connected to the connection line between the drain of the NMOS transistor M5 and the source of the upper driving transistor M9, the source is connected to the high side of the level shifting module, and the drain is connected to the connection line between the gate of the NMOS transistor M5 and the source of the upper driving transistor M8. The source of the NMOS transistor M5 is connected to the high side of the level shifting module; The upper driving transistor M8 has its gate connected to the first clamping voltage of the corresponding clamping submodule, its drain connected to the drain of the lower driving transistor M11, and its source serving as the first output terminal of the level shifting module. The upper driving transistor M9 has its gate connected to the first clamping voltage of the corresponding clamping submodule, its drain connected to the drain of the lower driving transistor M12, and its source serving as the second output terminal of the level shifting module. The gate of the lower driving transistor M11 is connected to the second clamping voltage of the corresponding clamping submodule, and the source is connected to the drain of the lower driving transistor M13. The lower driving transistor M11 is used to control the gate-source voltage of the lower driving transistor M13 according to the second clamping voltage. The lower driving transistor M12 has its gate connected to the second clamping voltage of the corresponding clamping submodule, and its source connected to the drain of the lower driving transistor M14. The lower driving transistor M12 is used to control the gate-source voltage of the lower driving transistor M14 according to the second clamping voltage. The gate of the lower driving transistor M13 is the first input terminal of the level shifting module, and the source is connected to the low side of the level shifting module. The lower driving transistor M14 has its gate as the second input terminal of the level shifting module and its source connected to the low-side terminal of the level shifting module.

7. The driving circuit according to claim 5, characterized in that, The first clamping branch includes: a Zener diode D1 and a resistor R1; The Zener diode D1 has its cathode connected to the high side of the level shifting module and its anode connected to one end of the resistor R1. The anode serves as the output terminal of the first clamping branch, used to output the first clamping voltage. The other end of the resistor R1 is connected to the low end of the level shifting module; The second clamping branch includes: resistor R2 and Zener diode D2; The resistor R2 is connected at one end to the high side of the level shifting module and at the other end to the cathode of the Zener diode D2. The Zener diode D2 has its anode connected to the low-side terminal of the level shifting module. The anode serves as the output terminal of the second clamping branch, used to output the second clamping voltage.

8. The driving circuit according to claim 1, characterized in that, The driving module includes: PMOS transistor M2, PMOS transistor M3, NMOS transistor M6 and NMOS transistor M7; The gate of the PMOS transistor M2 is connected to the gate of the NMOS transistor M6, the drain is connected to the drain of the NMOS transistor M6, and the source is connected to the high side of the last stage level shifting module. The gate of the PMOS transistor M2 serves as an input terminal of the driving module and is connected to the second output terminal of the last stage level shifting module. The drain of the PMOS transistor M2 serves as an output terminal of the driving module and is connected to the power switch. The gate of the PMOS transistor M3 is connected to the gate of the NMOS transistor M7, the drain is connected to the drain of the NMOS transistor M7, and the source is connected to the high side of the last stage level shifting module. The gate of the PMOS transistor M3 serves as another input terminal of the driving module and is connected to the first output terminal of the last stage level shifting module. The drain of the PMOS transistor M3 serves as another output terminal of the driving module and is connected to the power switch. The source of the NMOS transistor M6 is connected to the first clamping voltage of the last stage clamping submodule; The source of the NMOS transistor M7 is connected to the first clamping voltage of the last stage clamping submodule.

9. A drive system, characterized in that, include: Power supply, power switch and drive circuit as described in any one of claims 1-8; The input terminal of the power switch is connected to the drive circuit; The power supply is connected to the drive circuit and the power switch respectively. The power supply is used to provide operating voltage to the drive circuit and the power switch so that the drive circuit outputs a drive signal to the power switch to control the working state of the power switch.

10. A driving method based on the driving circuit according to any one of claims 1-8, characterized in that, include: Each clamping submodule in the clamping module provides a corresponding clamping voltage to the corresponding level shifting module. Based on the clamping voltage of each clamping submodule and the operating voltage provided by the external power supply, a multi-level level shifting module is used to sequentially convert the first and second control signals received by the first-level level shifting module into control signals with progressively increasing levels. The high-side terminal of the last-level level shifting module is connected to the operating voltage, and the voltage of the high-side terminal of each level shifting module increases progressively. Furthermore, the voltage of the high-side terminal of each level shifting module other than the last level shifting module is lower than the operating voltage. The drive module outputs a drive signal to an external power switch based on the control signal output by the last-stage level shift module, in order to control the working state of the power switch.

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