A drive arrangement and a converter

Abstract

A kind of driving device and converter, switch tube can be realized safe shutdown.The driving device includes driving push-pull circuit and miller clamp circuit;The input end of driving push-pull circuit receives driving signal, and the output end is connected with the control end of the controlled switch tube, for controlling the controlled switch tube to be turned on or be turned off when receiving driving signal;The first end of miller clamp circuit is connected with the input end of driving push-pull circuit, the second end is connected with the control end of the controlled switch tube, the third end is connected with negative power supply, when receiving the preset time length of driving signal for controlling the controlled switch tube to be turned off, control the switch tube that is connected between the second end and the third end is turned on.When driving device controls the controlled switch tube to be closed, miller clamp circuit establishes a low impedance loop for the control end of the controlled switch tube, the voltage generated by miller capacitor current on the low impedance loop is less than the voltage drop required for the controlled switch tube to be turned on, to avoid the controlled switch tube to be turned on mistakenly.

Description

Technical Field

[0001] This application relates to the field of power supply technology, and in particular to a drive device and a converter. Background Technology

[0002] In the power supply field, converters are typically used to convert between the power supply voltage and the load supply voltage. Converters generally have multiple bridge arms, each consisting of two switching transistors connected in series. These two transistors conduct complementaryly. When one transistor in a bridge arm changes from off to on, and the other changes from on to off, a Miller capacitance current is generated in the line. This current, when passing through the gate circuit of the transistor in the bridge arm, may produce a voltage drop greater than the threshold voltage of the off transistor, causing the off transistor to mis-turn on. In this case, the two transistors in the two bridge arms are directly connected, affecting the normal operation of the equipment and, in severe cases, causing equipment damage. Utility Model Content

[0003] This application provides a drive device and a converter for safely turning off a controlled switch, ensuring that the equipment containing the controlled switch can operate normally.

[0004] In a first aspect, embodiments of this application provide a driving device that can be applied to a converter to control the on / off switching of bridge arm switches in the converter. When a Miller capacitance current is generated at the control terminal of the controlled switch during the turn-off process, the driving device can clamp the control terminal of the controlled switch to prevent the controlled switch from falsely turning on and to ensure the normal operation of the equipment to which the controlled switch belongs. The driving device may include a drive push-pull circuit and a Miller clamping circuit.

[0005] The drive push-pull circuit has an input terminal for receiving drive signals and an output terminal for connecting to the control terminal of the controlled switch. Upon receiving a drive signal, the drive push-pull circuit controls the controlled switch to turn on or off. The Miller clamp circuit has a first terminal connected to the input terminal of the drive push-pull circuit, a second terminal connected to the control terminal of the controlled switch, and a third terminal connected to a negative power supply. When the drive push-pull circuit receives a drive signal for a preset duration to control the controlled switch to turn off, the Miller clamp circuit controls the switch connected between the second and third terminals to turn on.

[0006] With the above design, when the controller connected to the drive device sends a drive signal to the drive push-pull circuit to control the turn-off of the controlled switch, the drive push-pull circuit operates and constructs a discharge path for the control terminal of the controlled switch. When the charge stored at the control terminal of the controlled switch is completely released, the controlled switch turns off. Simultaneously, when the controlled switch is about to turn off, the Miller clamping circuit activates to create a low-impedance loop for the control terminal of the controlled switch. At this time, even if a Miller capacitance current occurs, the voltage generated by this current in the low-impedance loop cannot reach the threshold voltage required for the controlled switch to turn on, thereby preventing the controlled switch from being mis-turned on and ensuring normal circuit operation.

[0007] In one possible design, the driving signals include a first driving signal and a second driving signal. The drive push-pull circuit is specifically used to: upon receiving the first driving signal, create a charging path for the control terminal of the controlled switch; and when the control terminal of the controlled switch is fully charged, turn the controlled switch on. Upon receiving the second driving signal, the drive push-pull circuit creates a discharging path for the control terminal of the controlled switch; and when the control terminal of the controlled switch is fully discharged, turn the controlled switch off. The first driving signal can be a high-level signal, and the second driving signal can be a low-level signal.

[0008] In one possible design, the drive push-pull circuit includes a push-pull circuit and a drive resistor. The input terminal of the push-pull circuit receives the drive signal, and the output terminal of the push-pull circuit is connected to the control terminal of the controlled switch transistor through the drive resistor. With this design, the push-pull circuit internally includes two transistors connected in series, which can be connected to positive and negative power supplies respectively. The positive power supply, together with the drive resistor, forms a charging path for the control terminal of the controlled switch transistor, driving it to conduct. The negative power supply, together with the drive resistor, forms a discharging path for the control terminal of the controlled switch transistor, driving it to turn off.

[0009] In one possible design, the drive push-pull circuit includes an on circuit and an off circuit.

[0010] The circuit has the following configuration: the input terminal of the turn-on circuit receives the drive signal, and the output terminal of the turn-on circuit is connected to the control terminal of the controlled switch. The turn-on circuit controls the controlled switch to turn on when it receives the first drive signal. The circuit also has the following configuration: the input terminal of the turn-off circuit receives the drive signal, and the output terminal of the turn-off circuit is connected to the control terminal of the controlled switch. The turn-off circuit controls the controlled switch to turn off when it receives the second drive signal.

[0011] In one possible design, the Miller clamping circuit includes: a delay circuit, a fast turn-off circuit, and a second switching transistor.

[0012] Wherein, the first end of the delay circuit is connected to the input end of the drive push-pull circuit, and the second end of the delay circuit is connected to the control end of the controlled switch; the first end of the fast turn-off circuit is connected to the input end of the drive push-pull circuit, and the second end of the fast turn-off circuit is connected to the control end of the second switch; the first end of the second switch is used to connect to the control end of the controlled switch, the second end of the second switch is used to connect to the negative power supply, and the control end of the second switch is connected to the intermediate node of the delay circuit.

[0013] With the above design, when the second drive signal for controlling the turn-off of the controlled switch is received, the second switch is delayed in turn-on via a delay circuit to form a low-impedance loop. This ensures that the voltage drop generated by the Miller capacitor current passing through the low-impedance loop is less than the turn-on voltage drop of the controlled switch. Simultaneously, since the second switch can be delayed until the controlled switch is completely or about to be completely turned off, the turn-on of the third switch can be prevented from affecting the normal turn-off process of the controlled switch. When the first drive signal for controlling the turn-on of the controlled switch is received, the second switch is quickly turned off via a fast turn-off circuit, preventing the drive current used to drive the controlled switch from flowing to the second switch and ensuring the normal turn-on of the controlled switch.

[0014] In one possible design, the delay circuit can employ an industry-standard RC delay structure, for example, the delay circuit includes a first resistor and a first capacitor.

[0015] Wherein, the first end of the first resistor is connected to the input end of the drive push-pull circuit, the second end of the first resistor is connected to the control end of the second switch and the first end of the first capacitor; the second end of the first capacitor is connected to the control end of the controlled switch.

[0016] In one possible design, the fast shutdown circuit includes a second capacitor and a diode.

[0017] The first end of the second capacitor is connected to the input end of the drive push-pull circuit, and the second end of the second capacitor is connected to the anode of the diode; the cathode of the diode is connected to the control end of the second switching transistor.

[0018] In one possible design, the controlled switch is an IGBT or a MOSFET, and the switch in the Miller clamp circuit is a MOSFET or a transistor.

[0019] Secondly, embodiments of this application provide a converter comprising multiple bridge arms and multiple drive devices provided in the first aspect of this application and any possible design thereof. Each drive device is used to control the on / off switching of a switching transistor in one bridge arm.

[0020] Furthermore, the technical effects of the second aspect and any of its possible designs can be found in the technical effects of different designs in the first aspect of the embodiments of this application, and will not be repeated here. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the structure of a driving device provided in an embodiment of this application. Figure 1 ;

[0023] Figure 2 A schematic diagram of a drive push-pull circuit provided in an embodiment of this application. Figure 1 ;

[0024] Figure 3 A schematic diagram of a drive push-pull circuit provided in an embodiment of this application. Figure 2 ;

[0025] Figure 4 A schematic diagram of the structure of a Miller clamping circuit provided in this application embodiment. Figure 1 ;

[0026] Figure 2 A schematic diagram of a Miller clamping circuit provided in an embodiment of this application. Figure 1 . Detailed Implementation

[0027] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0028] The application scenarios of the technical solutions in the embodiments of this application will be described below with reference to the accompanying drawings. The solutions provided in the embodiments of this application can be applied to power supply systems, and the power supply system is equipped with a converter for realizing the conversion between the supply voltage and the load supply voltage.

[0029] In practical applications, converters typically include at least two bridge arms, each with two switching transistors connected in series: an upper bridge arm transistor and a lower bridge arm transistor. These two transistors can be metal-oxide-semiconductor field-effect transistors (MOSFETs), and they conduct complementaryly. When one transistor in a bridge arm switches from off to on, and the other switches from on to off, a Miller capacitance current is generated in the main circuit of the bridge arm. This Miller capacitance current can flow to the control terminal of the off-state transistor through its parasitic capacitance. When passing through the discharge circuit of the off-state transistor's control terminal, a voltage drop greater than the turn-on threshold voltage may occur, causing the off-state transistor to mis-turn on. In this case, the external power supply to the converter is directly short-circuited through the two transistors connected in series on the bridge arm, causing damage to multiple components.

[0030] Based on this, embodiments of this application provide a driving device and a converter for constructing a low-impedance loop. When the control terminal of the controlled switch tube flows through the Miller capacitance current during the turn-off process, the control terminal of the controlled switch tube is clamped by the aforementioned low-impedance loop to ensure that the voltage at the control terminal of the controlled switch tube is less than the conduction voltage, thereby preventing the controlled switch tube from being falsely turned on.

[0031] See Figure 1 The diagram shown is a structural schematic of a driving device provided in an embodiment of this application. This driving device can be connected to a controlled switch transistor and is used to control the switching on and off of the controlled switch transistor. The controlled switch transistor is one of the switches in the aforementioned bridge arm. Figure 1 As shown, the drive device may include a drive push-pull circuit and a Miller clamping circuit.

[0032] The input terminal of the drive push-pull circuit is used to receive the drive signal, and the output terminal of the drive push-pull circuit is used to connect to the control terminal of the controlled switch. The drive push-pull circuit is used to control the controlled switch to turn on or off when it receives the drive signal. The first terminal of the Miller clamp circuit is connected to the input terminal of the drive push-pull circuit, the second terminal of the Miller clamp circuit is used to connect to the control terminal of the controlled switch, and the third terminal of the Miller clamp circuit is used to connect to the negative power supply. The Miller clamp circuit is used to control the switch connected between the second and third terminals inside the Miller clamp circuit to turn on after the drive push-pull circuit receives the drive signal used to control the controlled switch to turn off for a preset time.

[0033] In practical use, the push-pull circuit in the drive device can be connected to an external controller. This controller can provide drive signals for turning the controlled switch on and off. These drive signals can include a first drive signal and a second drive signal. When the push-pull circuit receives the first drive signal, it controls the controlled switch to turn on; and when it receives the second drive signal, it controls the controlled switch to turn off.

[0034] In practical applications, the various circuits in the drive device can be independent circuits. For example, the controller can be packaged in the driver chip, and the drive push-pull circuit and Miller clamp circuit can be used as peripheral circuits of the driver chip, connected to the controller through the external pins of the driver chip. Alternatively, the various circuits in the drive device can be packaged with the controller as a single unit. For example, the controller, drive push-pull circuit, and Miller clamp circuit can all be packaged within the driver chip, and the controlled switching transistor can be connected to the various circuits within the drive device through the external pins of the driver chip.

[0035] use Figure 2 The drive device shown can be connected to an external controller. When it is necessary to control the controlled switch to turn on, the controller outputs a first drive signal to drive the push-pull circuit and charge the control terminal of the controlled switch. When the control terminal of the controlled switch is charged to the voltage required for conduction, the controlled switch turns on. When it is necessary to control the controlled switch to turn off, the controller outputs a second drive signal to drive the push-pull circuit and discharge the control terminal of the controlled switch. When the control terminal of the controlled switch is fully discharged, the controlled switch turns off. Simultaneously, the drive signal sent by the controller is also transmitted to the Miller clamping circuit through the input terminal of the drive push-pull circuit. The Miller clamping circuit can be configured with a delay device. This delay device can delay the reception of the second drive signal for a preset time before controlling the switch in the Miller clamping circuit to conduct, forming a low-impedance loop between the control terminal of the controlled switch and the negative power supply. Therefore, even if the state switching of the switch on the bridge arm causes the control terminal of the controlled switch to flow with Miller capacitor current, the Miller capacitor current cannot generate the voltage drop required for the controlled switch to conduct when passing through the above-mentioned low-impedance loop. This can effectively prevent the controlled switch from being mis-conducted, and the equipment to which the controlled switch belongs can also operate normally.

[0036] It should be noted that the controlled switch can be a metal-oxide-semiconductor field-effect transistor (MOSFET) or an insulated-gate bipolar transistor (IGBT). When the controlled switch is a MOSFET or an IGBT, the control terminal of the controlled switch is the gate of the MOSFET or the IGBT. To facilitate understanding of the technical solution claimed in this application, this application will use a MOSFET as an example for illustration.

[0037] The following section provides a detailed explanation of the process of turning the controlled switch on and off, taking into account the structure of each circuit in the drive device.

[0038] I. Drive Push-Pull Circuit

[0039] The input of the push-pull drive circuit can be connected to an external controller, and the output can be connected to the control terminal of the controlled transistor. Upon receiving the first drive signal from the controller, the push-pull drive circuit charges the control terminal of the controlled transistor. When the control terminal reaches the voltage required for conduction, the controlled transistor turns on. Upon receiving the second drive signal from the controller, the push-pull drive circuit discharges the control terminal of the controlled transistor. When the discharge is complete, the controlled transistor turns off.

[0040] The push-pull drive circuit can adopt the industry-standard push-pull drive structure topology.

[0041] In some implementations, in order to enable the controlled switch to have separate turn-on and turn-off paths, the drive push-pull circuit may include a turn-on circuit and a turn-off circuit.

[0042] The circuit consists of an input terminal for receiving a drive signal and an output terminal for connecting to the control terminal of the controlled switch. The control circuit is used to turn on the controlled switch when it receives the first drive signal. The circuit also consists of an input terminal for receiving a drive signal and an output terminal for connecting to the control terminal of the controlled switch. The control circuit is used to turn off the controlled switch when it receives the second drive signal.

[0043] See Figure 2 The diagram shown is a schematic representation of a push-pull drive circuit according to an embodiment of this application. Transistor T1, resistors Rb1 and Rz1 form the conduction circuit of the controlled switch Q1, and transistor T2, resistors Rb2 and Rz2 form the turn-off circuit of the controlled switch Q2. Power supply VCC1 is a positive power supply, and power supply VCC2 is a negative power supply.

[0044] See also Figure 2 As shown, resistor Rb1 is the bias resistor for transistor T1, and resistor Rz1 is the drive resistor in the conduction path of the controlled switch Q1. When the controller sends the first drive signal, the first drive signal provides a bias voltage to the base of transistor T1 through the bias resistor Rb1, turning on transistor T1 and driving the controlled switch Q1 to conduct. Resistor Rb2 is the bias resistor for transistor T2, and resistor Rz2 is the drive resistor in the turn-off path of the controlled switch Q1. When the controller sends the second drive signal, the second drive signal provides a bias voltage to the base of transistor T2 through the bias resistor Rb2, turning on transistor T3 and driving the controlled switch Q1 to turn off.

[0045] Specifically, through Figure 2 The push-pull circuit shown controls the controlled switch Q1, taking the first drive signal for turning on Q1 as a high-level signal and the second drive signal for turning off Q1 as a low-level signal as an example. When the controller outputs the first drive signal, transistor T1 conducts, forming an electrical connection between power supply VCC1 and the controlled switch Q1. Power supply VCC1 charges the control terminal of the controlled switch Q1 through transistor T1 and resistor Rz1. When the control terminal of the controlled switch Q1 is charged to the threshold voltage required for conduction, the controlled switch Q1 conducts. When the controller outputs the second drive signal, transistor T2 conducts, forming an electrical connection between power supply VCC2 and the controlled switch Q1. Transistor T2 and resistor Rz2 discharge the control terminal of the controlled switch Q1. When the control terminal of the controlled switch Q1 has finished discharging, the controlled switch Q1 turns off.

[0046] It should be noted that the above Figure 3 The push-pull circuit structure shown is merely an example. In practical applications, other commonly used drive structure topologies can be selected. For instance, in a push-pull circuit, the drive resistors and bias resistors on the turn-on and turn-off circuits can be reused. That is, the push-pull circuit includes a drive resistor Rz and a push-pull circuit composed of transistors T1 and T2 and bias resistors Rb for the two transistors T1 and T2. Specifically, the structure of the push-pull circuit can be found in [reference needed]. Figure 2 As shown.

[0047] It should be noted that the above Figure 3 and Figure 4 The push-pull circuit structure shown is only an example. In actual applications, the structure of the push-pull circuit can be other commonly used drive structure topologies in the industry. This application does not make any specific restrictions here.

[0048] II. Miller Clamping Circuit

[0049] The first terminal of the Miller clamp circuit is connected to the input terminal of the push-pull drive circuit, the second terminal is connected to the control terminal of the controlled switch, and the third terminal is connected to the negative power supply VCC2 connected to the push-pull drive circuit. The Miller clamp circuit can control the switch connected between the second and third terminals to turn on after a preset time following the driver receiving the second drive signal from the controller. This provides a low-impedance loop for the controller of the controlled switch, ensuring that when a Miller capacitor current appears at the control terminal during the turn-off process of the controlled switch, the voltage drop generated by the Miller capacitor current in the aforementioned low-impedance loop is less than the turn-on voltage of the controlled switch. This prevents the controlled switch from being mis-turned on and ensures that the device containing the controlled switch can operate normally.

[0050] For practical applications, please refer to Figure 5 As shown, the Miller clamping circuit may include a delay circuit, a fast turn-off circuit, and a second switch Q2.

[0051] Specifically, the first end of the delay circuit is connected to the input end of the drive push-pull circuit, and the second end of the delay circuit is connected to the control end of the controlled switch. The first end of the fast turn-off circuit is connected to the input end of the drive push-pull circuit, and the second end of the fast turn-off circuit is connected to the control end of the second switch. The first end of the second switch Q2 can be connected to the control end of the controlled switch, the second end of the second switch is connected to the power supply VCC2, and the control end of the second switch is connected to the intermediate node of the delay circuit.

[0052] The purpose of the delay circuit is as follows: When the drive device receives the second drive signal from the external controller, this second drive signal can be delayed for a preset time before driving the second switch to turn on, providing a low-impedance loop for the control terminal of the controlled switch. At this time, the controlled switch has been completely turned off or is about to be completely turned off, ensuring that the low-impedance loop will not conduct during the initial turn-off phase of the controlled switch, allowing the controlled switch to be safely turned off. The purpose of the fast turn-off circuit is as follows: Since the second switch provides a low-impedance loop for the control terminal of the controlled switch, when the drive signal received by the drive device changes from the second drive signal to the first drive signal, if the second switch is still in the on state, the drive current used to drive the controlled switch to turn on will directly pass through the low-impedance loop, preventing the drive current from charging the control terminal of the controlled switch and affecting its normal conduction. The fast turn-off circuit can control the second switch to turn off quickly when the drive signal received by the drive device changes from the second drive signal to the first drive signal, ensuring the normal conduction of the controlled switch.

[0053] In one example, the delay circuit can adopt the industry-standard RC delay structure, which includes a first resistor and a first capacitor. The first end of the first resistor is connected to the input of the drive push-pull circuit, and the second end of the first resistor is connected to the control terminal of the second switch and the first end of the first capacitor; the second end of the first capacitor is connected to the control terminal of the controlled switch.

[0054] In one example, the fast turn-off circuit may include a second capacitor and a diode. The first terminal of the second capacitor is connected to the input terminal of the drive push-pull circuit, and the second terminal of the second capacitor is connected to the anode of the diode; the cathode of the diode is connected to the control terminal of the second switching transistor.

[0055] To facilitate understanding, a specific example of a Miller clamping circuit is given below.

[0056] See Figure 5 The diagram shown is a schematic representation of a Miller clamping circuit provided in an embodiment of this application. Figure 5 In this circuit, resistor R1 can be considered as the first resistor, capacitor C1 can be considered as the first capacitor, capacitor C2 can be considered as the second capacitor, and transistor Q2 can be considered as the second switching transistor.

[0057] It should be noted that, Figure 5 The second switching transistor in the Miller clamping circuit shown is a transistor for example only. In actual applications, the second switching transistor can also be a MOSFET, or other switching transistors driven in the above manner can be selected. This application does not impose any restrictions here.

[0058] use Figure 5 When the Miller clamp circuit shown controls the controlled switch, taking the first drive signal used to turn on the controlled switch Q1 as a high-level signal and the second drive signal used to turn off the controlled switch Q2 as a low-level signal as an example, when the Miller clamp circuit receives the second drive signal sent by the controller, there is a voltage difference between the control terminal of the controlled switch Q1 and the second drive signal. This voltage difference charges capacitor C1 through the path formed by resistor R1 and capacitor C1. As the charging time increases, the first terminal of capacitor C1 is connected to the base potential of transistor Q2. As the voltage gradually decreases, when the base potential of transistor Q2 meets the conduction requirement, transistor Q2 conducts and connects the control terminal of the controlled switch Q1 to the power supply VCC2. Therefore, if Miller capacitance current appears at the control terminal of the controlled switch Q1, this Miller capacitance current will preferentially flow to the low impedance path formed by transistor Q2. Since the on-resistance of transistor Q2 is small, the voltage drop generated when the Miller capacitance current passes through transistor Q2 is less than the conduction voltage amplitude requirement of the controlled switch Q1, which can effectively avoid the situation where the controlled switch Q1 is mis-turned on.

[0059] See also ​As shown, when the Miller clamping circuit receives the first drive signal sent by the controller, the second drive signal can quickly raise the base potential of transistor Q2 through capacitor C2 and diode D, thereby quickly controlling transistor Q2 to turn off. This prevents the drive current transmitted by power supply VCC1 through resistor Rz from flowing to transistor Q2. The drive current flows normally to the control terminal of the controlled switch Q1 and charges the control terminal of the controlled switch Q1, ensuring that the controlled switch Q1 can conduct normally.

[0060] It should be noted that the types of resistor R1 and capacitor C1 can be configured according to the turn-off time of the controlled switch Q1 and the on-state voltage drop of transistor Q2. For example, to avoid affecting the normal turn-off process of the controlled switch Q1, the time for resistor R1 and capacitor C1 to charge to the on-state voltage drop of transistor Q2 should be less than or equal to the time required for the control terminal of the controlled switch Q1 to discharge completely. For example, if the turn-off time of the controlled switch Q1 is 10µs, by selecting appropriate types of resistor R1 and capacitor C1, the time for capacitor C2 to charge to the on-state voltage drop of transistor Q2 can be configured to be 10µs or 9.5µs. Therefore, the Miller clamping circuit structure described above will activate Miller clamping only when the controlled switch is completely turned off or about to be completely turned off, thus not affecting the normal turn-off process of the controlled switch and ensuring that the device containing the controlled switch can operate normally.

[0061] Of course, the above description of the Miller clamp circuit structure is only an example. In practical applications, the Miller clamp circuit can also adopt other structures. For example, the second switch Q2 in the Miller clamp circuit can also be a MOSFET or other devices in the industry that have the above functions.

[0062] Based on the above description, embodiments of this application also provide a converter that can be applied to a power supply system and used to convert between the supply voltage and the load voltage. The converter includes at least multiple bridge arms and multiple of the aforementioned drive push-pull circuits. Each drive push-pull circuit can correspond one-to-one with a specific bridge arm, and each bridge arm can be used to control the on / off state of the switching transistor in its corresponding bridge arm.

[0063] It should be noted that the converter consisting of bridge arms and drive units is only one structural topology for converters. In practical applications, converters can also have other structural topologies. For example, in addition to the aforementioned components, the converter can also include energy storage inductors corresponding to each bridge arm. These energy storage inductors can form a power factor correction (PFC) circuit with the corresponding bridge arm to improve the converter's operating efficiency. Of course, converters can also adopt other topologies with the above functions, which will not be described in detail here.

[0064] In practical applications, converters may also include other functional devices, such as protection devices, which can be overload protection devices and short-circuit protection devices.

[0065] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of different embodiments are consistent and can be referenced by each other. The technical features of different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0066] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of protection of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A driving device, characterized in that, include: Drive push-pull circuit and Miller clamp circuit; The input terminal of the drive push-pull circuit is used to receive drive signals, and the output terminal of the drive push-pull circuit is used to connect to the control terminal of the controlled switch. The drive push-pull circuit is used to control the controlled switch to be turned on or off when it receives a drive signal. The first terminal of the Miller clamping circuit is connected to the input terminal of the drive push-pull circuit. The second terminal of the Miller clamping circuit is used to connect to the control terminal of the controlled switch. The third terminal of the Miller clamping circuit is used to connect to the negative power supply. The Miller clamping circuit is used to control the switch connected between the second and third terminals inside the Miller clamping circuit to conduct after the drive push-pull circuit receives a drive signal for controlling the controlled switch to turn off for a preset duration.

2. The apparatus according to claim 1, characterized in that, The driving signal includes a first driving signal and a second driving signal. The driving push-pull circuit is specifically used to: control the controlled switch to turn on when the first driving signal is received, and control the controlled switch to turn off when the second driving signal is received.

3. The apparatus according to claim 1 or 2, characterized in that, The drive push-pull circuit includes a push-pull circuit and a drive resistor. The input terminal of the push-pull circuit is used to receive the drive signal, and the output terminal of the push-pull circuit is connected to the control terminal of the controlled switch through the drive resistor.

4. The apparatus according to claim 2, characterized in that, The drive push-pull circuit includes: an on circuit and an off circuit; The input terminal of the conduction circuit is used to receive the driving signal, and the output terminal of the conduction circuit is used to connect to the control terminal of the controlled switch. The conduction circuit is used to control the controlled switch to conduct when the first driving signal is received. The input terminal of the shutdown circuit is used to receive the drive signal, and the output terminal of the shutdown circuit is used to connect to the control terminal of the controlled switch. The shutdown circuit is used to control the controlled switch to turn off when the second drive signal is received.

5. The apparatus according to claim 1, characterized in that, The Miller clamping circuit includes: a delay circuit, a fast turn-off circuit, and a second switching transistor; The first end of the delay circuit is connected to the input end of the drive push-pull circuit, and the second end of the delay circuit is connected to the control end of the controlled switch. The first terminal of the fast shutdown circuit is connected to the input terminal of the drive push-pull circuit, and the second terminal of the fast shutdown circuit is connected to the control terminal of the second switching transistor. The first end of the second switch is used to connect to the control end of the controlled switch, the second end of the second switch is used to connect to the negative power supply, and the control end of the second switch is connected to the intermediate node of the delay circuit.

6. The apparatus according to claim 5, characterized in that, The delay circuit includes: a first resistor and a first capacitor; The first end of the first resistor is connected to the input end of the drive push-pull circuit, and the second end of the first resistor is connected to the control end of the second switch and the first end of the first capacitor. The second terminal of the first capacitor is connected to the control terminal of the controlled switch transistor.

7. The apparatus according to claim 5 or 6, characterized in that, The fast shutdown circuit includes: a second capacitor and a diode; The first terminal of the second capacitor is connected to the input terminal of the drive push-pull circuit, and the second terminal of the second capacitor is connected to the anode of the diode. The cathode of the diode is connected to the control terminal of the second switching transistor.

8. The apparatus according to claim 1, characterized in that, The controlled switching transistor is an IGBT or a MOSFET, and the switching transistor in the Miller clamping circuit is a MOSFET or a transistor.

9. A converter, characterized in that, include: Multiple bridge arms and multiple drive devices as described in any one of claims 1 to 8, each drive device being used to control the on and off of a switching transistor in one bridge arm.

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