Driving device and power transmission device

Abstract

The embodiment of the invention provides a driving device and power transmission equipment. The driving apparatus includes a main driving circuit coupled between a first reference potential and a second reference potential and configured to form a current path from the first reference potential to a gate of a power switching device based on a first signal for turning on the power switching device, and forming a current path from the gate to a second reference potential based on a second signal for turning off the power switching device, the second reference potential being lower than the first reference potential; and a first auxiliary driving circuit coupled between the gate and a third reference potential, and configured to form a current path from the gate to the third reference potential based on the second signal and based on a potential of the gate being higher than the third reference potential, the third reference potential being lower than the first reference potential and higher than the second reference potential. According to the embodiment of the invention, multiple performances such as switching loss and response speed of the power switching device can be effectively improved.

Description

Technical Field

[0001] The present disclosure relates to power electronic technology, and more particularly, to a driving device for a power switching device and a power transmission device including the driving device. Background Art

[0002] Power switching devices usually require a pre-stage drive circuit to drive and control their on and off. In some application scenarios (such as automotive high-side switch products), power switching devices need to drive inductive or resistive loads, and in order to prevent overshoot and prevent the switch itself or the subsequent circuit from being damaged due to overvoltage, the drive circuit of the power switching device needs to implement slow opening and / or slow shutdown functions. In addition, in order to ensure that the switch has a higher operating frequency and smaller switching loss in some modes (such as PWM control mode), the turn-on rate and / or turn-off rate of the drive circuit cannot be too slow. In other words, the drive circuit needs to have a certain turn-on rate and / or turn-off rate control capability.

[0003] However, due to the different characteristics of different transition stages during the turn-on or turn-off process, it is difficult to achieve more accurate rate control with current drive schemes. The power switch device stays too long in some transition stages, which increases the switching loss of the power switch and affects the switch response time. Summary of the invention

[0004] In order to at least partially solve the above-mentioned and other possible problems, embodiments of the present disclosure provide a driving device and a power transmission device including the driving device.

[0005] According to a first aspect of the present disclosure, a driving device is provided. The driving device includes: a main driving circuit coupled between a first reference potential and a second reference potential, and configured to form a current path from the first reference potential to the gate of the power switching device based on a first signal for turning on the power switching device, and to form a current path from the gate to a second reference potential based on a second signal for turning off the power switching device, the second reference potential being lower than the first reference potential; and a first auxiliary driving circuit coupled between the gate and a third reference potential, and configured to form a current path from the gate to the third reference potential based on the second signal and based on the gate potential being higher than the third reference potential, the third reference potential being lower than the first reference potential and higher than the second reference potential.

[0006] According to a second aspect of the present disclosure, a driving device is provided. The driving device includes: a main driving circuit, coupled between a first reference potential and a second reference potential, and configured to form a current path from the first reference potential to the gate of the power switching device based on a first signal for turning on the power switching device, and to form a current path from the gate to the second reference potential based on a second signal for turning off the power switching device, the second reference potential being lower than the first reference potential; and a second auxiliary driving circuit, configured to form a current path from the first reference potential to the gate based on the first signal and based on the gate potential being higher than a threshold potential, the threshold potential being lower than the first reference potential and higher than the second reference potential, the second auxiliary driving circuit including: a second switching branch, including a second switching tube coupled between the first reference potential and the gate; a potential monitoring branch, coupled between the first reference potential and the gate, and configured to monitor the gate potential based on the first signal; a second control branch, coupled between the first reference potential and the second reference potential or the third reference potential, and configured to control the second switching tube to turn on based on the potential monitored by the potential monitoring branch exceeding the threshold potential.

[0007] According to a third aspect of the present disclosure, a power transmission device is provided, comprising: a power switching device; and a driving device according to the first aspect or the second aspect, coupled to a gate of the power switching device.

[0008] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the disclosure, nor is it intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0010] Figure 1 A schematic circuit diagram of a power transmission device is shown.

[0011] Figure 2 The waveform diagrams of the gate potential, the output potential, the on-control signal and the off-control signal during the operation of the power switch device are shown.

[0012] Figure 3 A schematic circuit diagram of a power transmission device according to an embodiment of the present disclosure is shown.

[0013] Figure 4 A schematic circuit diagram of a power transmission device according to an embodiment of the present disclosure is shown.

[0014] Figure 5 A schematic circuit diagram of a power transmission device according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0015] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art. Those skilled in the art can obtain alternative technical solutions from the following description without departing from the spirit and scope of protection of the present disclosure.

[0016] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one example embodiment". Other explicit and implicit definitions may also be included below.

[0017] Figure 1 Schematic circuit diagram of power transmission device 10 ′ is shown. Figure 1 As shown, the power transmission device 10' includes a power switch device 110' and a load 120', and the power switch device 110' and the load 120' are connected in series between a power supply potential and a ground potential. The power transmission device 10' also includes a drive circuit 200', and the drive circuit 200' is connected to the gate of the power switch device 110' to drive the power switch device 110', so as to realize the on and off operation of the power switch device 110'. The drain D' of the power switch device 110' is connected to the power supply potential, and the source S' of the power switch device 110' is connected to the load 120' to provide an output voltage to the load 120', wherein the potential at the output node is the output potential V OUT In addition, the power switch device 110' has a parasitic capacitance C between its gate G' and drain D'. gd ', and has a parasitic capacitance C between its gate G' and source S' gs '.

[0018] The driving circuit 200' can provide a turn-on rate and / or turn-off rate control function. Specifically, the driving circuit 200' includes a switch SW1', a current source I1', a switch SW2' and a current source I2'. During the turn-on process of the power switch device 110', the switch SW1' can be closed under the control of the turn-on signal, and the driving circuit 200' uses the current of the current source I1' to control the parasitic capacitance C of the power switch device 110'. gd' and C gs ' to charge the power switch device 110' from the off state to the on state. By setting or adjusting the current of the current source I1', the parasitic capacitance C gd ' and C gs ', thereby controlling the turn-on rate of the power switch device 110'. During the turn-off process of the power switch device 110', the switch SW2' can be closed under the control of the turn-off signal, and the driving circuit 200' charges the parasitic capacitance C of the power switch device 110' with the current of the current source I2'. gd ' and C gs ' discharges to switch the power switch device 110' from the on state to the off state. By setting or adjusting the current size of the current source I2', the parasitic capacitance C gd ' and C gs ', thereby controlling the turn-off rate of the power switch device 110'.

[0019] Figure 2 shows the gate potential V during operation of the power switch device 110 ′ G ', output potential V OUT ', turn on the control signal G ON and the shutdown control signal G OFF As an example, the load 120' is a resistive load. The turn-on process of the power switch device 110' can be divided into three transition stages S1, S2 and S3, and the turn-off process of the power switch device 110' can also be divided into three transition stages S1', S2' and S3'.

[0020] In the first transition phase S1 of the turn-on process, the switch SW1' is closed (the switch SW2' is opened), so that the current source I1' supplies a constant current to the gate-source parasitic capacitance C of the power switch device 110'. gs ' and gate-drain parasitic capacitance C gd ' is charged, and the working state of the power switch device 110' changes from the cut-off region to the saturation region. In the second transition phase S2 of the turn-on process, the current source I1' uses a constant current as the gate-drain parasitic capacitance C gd ' until the working state of the power switch device 110' enters the linear region, at which time the source potential of the power switch device 110' is close to the drain potential. In the third transition phase S3 of the turn-on process, the constant current of the constant current source I1' continues to be the gate-source parasitic capacitance C gs ' and gate-drain parasitic capacitance C gd' until the power switch device 110' is fully turned on and enters the deep linear region. In the first transition stage S1', the second transition stage S2' and the third transition stage S3' of the shutdown process, the switch SW2' is closed (the switch SW1' is disconnected), and the constant current of the constant current source I2' discharges the parasitic capacitance, so that the power switch device 110' changes from fully turned on to fully turned off in the opposite state. The principle and state change of the shutdown process are similar to those of the connection process, so they are not repeated here.

[0021] Due to the different characteristics of each transition stage, it is difficult to achieve accurate turn-on rate control and / or turn-off rate control using a single current source. In addition, the gate-source parasitic capacitance C gs ' is usually larger, and in the first transition stage S1' of the turn-off and the third transition stage S3 of the turn-on, the gate-source voltage V gs There will be large changes, resulting in a longer stay in these two stages, which will increase the switching loss during the turn-on and turn-off process and affect the switch response time. In some control modes such as PWM mode, the maximum operating frequency of the switch will be affected and limited. In addition, for both turn-on and turn-off, in the process from the flip of the control signal to the flip of the output signal, the switch tube states of the two are different, resulting in the delay of the actual turn-on time being different from the delay of the actual turn-off time, causing the asymmetry of the turn-on process and the turn-off process, thus generating a duty cycle error. Staying in a part of the transition stage (such as the third stage of turn-on and the first stage of turn-off) for too long will increase this duty cycle error.

[0022] The embodiment of the present disclosure provides an improved driving scheme for a power switch device. In the improved scheme, in addition to the main driving circuit, a first auxiliary driving circuit is added, and the first auxiliary driving circuit is coupled between the gate of the power switch device and a third reference potential, which is lower than the first reference potential and higher than the second reference potential. Thus, an additional discharge path can be added in the initial transition stage of the shutdown to speed up the discharge process, thereby avoiding the switch from staying in the initial transition stage for too long when shutting down. Since the additional discharge path is coupled between the gate of the power switch device and the third reference potential, the additional discharge path will automatically stop discharging in the subsequent transition stage when the gate potential is lower, which ensures in a simple and effective way that the first auxiliary driving circuit only works in the slow initial transition stage without affecting the later transition stage. By setting the first auxiliary driving circuit, the initial transition stage can be accelerated and shortened during the shutdown, which helps to reduce switching losses, improve the response speed of the switch when shutting down, increase the switch operating frequency, and achieve more accurate shutdown rate control. In some embodiments of the present disclosure, a second auxiliary drive circuit is also provided, which can introduce an additional charging path in the later transition stage of the power switch device's turn-on process, thereby accelerating the charging process in the later transition stage and shortening the dwell time in this stage, thereby helping to reduce switching losses, improve the response speed when the switch is turned on, provide a switch operating frequency, and achieve more accurate turn-on rate control. In addition, since the initial transition stage of the turn-off process and / or the later transition stage of the turn-on process are shortened, it helps to reduce or eliminate the asymmetry of the turn-on and turn-off processes, thereby reducing or eliminating duty cycle errors.

[0023] Figure 3 FIG. 1 shows a schematic circuit diagram of a power transmission device 10 according to an embodiment of the present disclosure. Figure 3 As shown, the power transmission device 10 includes a power switch device 110 and a load 120. As an example, the power switch device 110 can be an N-type metal oxide semiconductor field effect transistor (MOSFET), and the load 120 can be a resistive and / or inductive load. However, it is understood that the power switch device 110 can be other suitable types of power switch devices, and the load 120 can be other types of loads. The power switch device 110 and the load 120 are coupled in series at a reference potential V REF4 With reference potential V REF2 For example, the reference potential V REF4 can be the power supply potential, and the reference potential V REF2 The power switch device 110 has a gate G, a drain D, a source S, a gate-source parasitic capacitance C gsand gate-drain parasitic capacitance C gd The drain D is coupled to the reference potential V REF4 , and the source S is coupled to the output node potential V OUT and a load 120. In addition, the power transmission device 10 further includes a driving device 200. The driving device 200 is coupled to the gate G of the power switching device 110, and is used to drive the power switching device 110 to switch the power switching device 110 on and off.

[0024] The driving device 200 includes a main driving circuit 210. The main driving circuit 210 is coupled to a reference potential V REF1 With reference potential V REF2 and based on the signal for turning on the power switch device 110, a reference potential V is formed. REF1 A current path is formed from the gate G to the reference potential V based on a signal for turning off the power switch device 110. REF2 The current path, where the reference potential V REF2 Below the reference potential V REF1 As an example, the reference potential V REF2 is the ground potential, and the reference potential V REF1 The main driving circuit 210 may include switch elements SW1 and SW2 and current sources I1 and I2. The switch element SW1 and the current source I1 are coupled in series to the reference potential V REF1 and the gate G of the power switch device 110, and the current source I2 and the switch element SW2 are coupled in series between the gate G and the reference potential V REF2 When the controller (not shown) of the power transmission device 10 or the power switch device 110 sends an on control signal or an off control signal (e.g. Figure 2 The high level active signal G ON or signal G OFF ), the main driving circuit 210 can perform corresponding operations to drive the power switch device 110. Specifically, when a control signal (hereinafter referred to as an ON signal) for turning on the power switch device 110 is sent to the driving device 200, the switch element SW1 will be controlled by the ON signal to be closed, and the switch element SW2 will remain open, so that the constant current of the current source I1 is increased from the reference potential V REF1 flows to the gate G and to the parasitic capacitance C of the power switch device 110 gs and C gsWhen a shutdown control signal (hereinafter referred to as OFF signal) is sent to the driving device 200 to shut down the power switch device 110, the switch element SW2 will be controlled by the OFF signal to be closed, and the switch element SW1 will remain open, so that the constant current of the current source I2 flows from the gate G to the reference potential V REF2 , and the parasitic capacitance C of the power switch device 110 gs and C gs Discharge. By setting the current of current source I1 and current source I2, the charging speed during the on process and the discharging speed during the off process can be adjusted. In another example, one or both of current sources I1 and I2 can be replaced with a resistor, or an additional series resistor can be added to one or both of current sources I1 and I2. By setting the resistance of the resistor or setting both the resistance of the resistor and the current of the current source, the charging speed during the on process and the discharging speed during the off process can also be adjusted.

[0025] The driving device 200 further includes a first auxiliary driving circuit 220. The first auxiliary driving circuit 220 is coupled between the gate G of the power switch device 110 and the reference potential V REF3 and based on the OFF signal for turning off the power switch device 110 and based on the potential of the gate G being higher than the reference potential V REF3 And form a voltage from gate G to reference potential V REF3 The reference potential V REF3 Below the reference potential V REF1 and is higher than the reference potential V REF2 .

[0026] As an example, the reference potential V REF1 、V REF2 and V REF4 can be a potential higher than the power supply potential (such as the boost potential of the charge pump), the ground potential, and the power supply potential, and the reference potential V REF3 It can be a power supply potential or other power rail potential generated based on the power supply potential, such as a power rail potential 5V lower than the power supply voltage. In one embodiment, the reference potential V REF3 is selected or set to indicate the end of the transition phase from the linear region to the saturation region of the power switch device 110. In other words, the reference potential V REF3 The first transition phase S1' (see Figure 2 ) ends the potential of the corresponding gate G. The output node potential V OUT Based on the potential V when the power switch device 110 is fully turned on OUT =V S -ILOAD *R on , where V S ,I LOAD and R on Respectively represent the power supply potential (for example, the reference potential V REF4 ), the current of the load 120 and the on-resistance of the power switch device 110. Further, the potential of the gate G at the end of the first transition phase S1' of the shutdown can be measured by V G =V OUT +V gs To estimate, where V gs Represents the gate-source voltage, V gs V can be determined by the current-voltage characteristic curve of the power switch device (such as MOSFET) and the load current, for example, by looking up a table, or the saturation current formula of the power switch device can be used to determine V G or V gs For example, the saturation current formula of MOSFET is I d =μ*Cox*W / L*(V G -V OUT -V TH ) 2 , where I d represents the drain current, μ represents the electron mobility, Cox represents the gate oxide capacitance per unit area, W / L represents the ratio of the oxide width to the length of the MOSFET, V TH is the threshold voltage of the MOSFET.

[0027] When the power switch device 110 is in a fully turned-on state, the potential of the gate G is approximately equal to the reference potential V REF1 , which is higher than the reference potential V REF3 In addition, the OFF signal for turning off the power switch device 110 can enable the first auxiliary drive circuit 220 to switch from the gate G to the reference potential V REF3 Thus, in addition to the discharge path provided by the main drive circuit 210, an additional discharge path can be introduced through the first auxiliary drive circuit 220 during the initial transition phase of turning off the power switch device 110, for example, Figure 2 The additional discharge path is introduced in the transition stage S1' shown. That is, in the initial transition stage of the shutdown process, the discharge path provided by the current source I2 and the switch element SW2 of the main drive circuit 210 and the discharge path additionally provided by the first auxiliary drive circuit 220 jointly perform discharge, which can accelerate the discharge of the parasitic capacitance of the power switch device 110 in the initial transition stage of the shutdown such as the transition stage S1', thereby shortening and controlling the duration of staying in the initial transition stage. As the discharge in the shutdown process continues, the potential of the gate G gradually decreases and will be lower than the reference potential VREF3 , whereby the discharge path provided by the first auxiliary drive circuit 220 can automatically stop running in the later transition stages (e.g., transition stages S2' and S3') of the shutdown process, and only the main drive circuit 210 performs the discharge, which avoids the first auxiliary drive circuit 220 affecting the subsequent transition stages. In this way, the duration of the initial transition stage of shutdown can be shortened and controlled, especially the duration of the transition stage S1' of shutdown or the duration of the power switch device from the linear region to the saturation region during the shutdown process, thereby reducing switching losses, improving the switching response speed and helping to increase the maximum operating frequency of the switch. In addition, as the duration of the initial transition stage of shutdown is shortened, it is also helpful to improve the asymmetry of the turn-on and turn-off processes, thereby reducing the duty cycle error.

[0028] Figure 4 FIG. 2 shows a schematic circuit diagram of a power transmission device 10 according to another embodiment of the present disclosure. Figure 3 The difference is that Figure 4 The driving device 200 of the power transmission device 10 in the embodiment further includes a second auxiliary driving circuit 230. The second auxiliary driving circuit 230 is coupled to the reference potential V REF1 and the gate G, and based on the ON signal for turning on the power switching device 110 and based on the potential of the gate G being higher than a predetermined threshold potential, a reference potential V is formed. REF1 The current path to the gate G. The predetermined threshold potential is lower than the reference potential V REF1 and is higher than the second reference potential V REF2 .

[0029] The predetermined threshold potential can be preset in the second auxiliary driving circuit 230 and can be set to be equal to the selected reference potential V REF3 In a similar manner, for example, the predetermined threshold potential can be set equal to the power supply potential or equal to other power rail potentials generated by the power supply potential. In one embodiment, the predetermined threshold potential can be set to indicate the beginning of the transition phase from the saturation region to the deep linear region of the power switch device 110. That is, the predetermined threshold potential can be set to be close to or equal to the third transition phase S3 of the on state (see Figure 2 ) starts with the corresponding gate potential V G , the gate potential V G The gate potential corresponding to the end of the first transition phase S1 ′ of the shutdown may be determined or calculated in the same manner as described above.

[0030] If the second auxiliary driving circuit 230 receives an ON signal for turning on the power switch device 110, and the potential of the gate G is higher than a predetermined threshold potential set inside the second auxiliary driving circuit 230, the second auxiliary driving circuit 230 will be enabled to switch from the reference potential VREF1 Thus, in addition to the charging path provided by the main driving circuit 210, an additional charging path can be introduced by the second auxiliary driving circuit 230 at a later transition stage of turning on the power switch device 110, for example, Figure 2 The additional charging path is introduced in the transition stage S3 shown. That is, in the later transition stage of the connection process, the charging path provided by the current source I1 and the switch element SW1 of the main drive circuit 210 and the charging path additionally provided by the second auxiliary drive circuit 230 perform charging together, which can accelerate the charging of the parasitic capacitance of the power switch device 110 in the later transition stage of the connection such as the transition stage S3, thereby shortening the duration of staying in the later transition stage. In addition, in the initial or early transition stage of the connection process (for example, the first transition stage S1 and the second transition stage S2 of the connection), the gate G is at a lower potential and is lower than the predetermined threshold potential, so that the additional charging path in the second auxiliary drive circuit 230 is not enabled in the initial or early transition stage, and the parasitic capacitance of the power switch device 110 is only charged by the main drive circuit 210, which avoids the second auxiliary drive circuit 230 affecting the initial or early transition stage. In this way, the duration of the later transition phase of the turn-on can be shortened and controlled, especially the duration of the turn-on transition phase S3 or the duration of the power switching device from the saturation region to the deep linear region during the turn-on process, thereby reducing switching losses, improving the switching response speed and helping to increase the maximum operating frequency of the switch.

[0031] In some embodiments of the present disclosure, the driving device 200 of the power transmission device 10 further includes a charge pump 240, which is coupled to the reference potential V REF1 and below the reference potential V REF1 The reference potential V REF4 As an example, in some cases, the source S of the power switch device 110 is in a suspended state and reaches the potential of the drain D. Therefore, in order to ensure that the power switch device 110 can be turned on, it is necessary to make the potential applied to the gate G higher than the potential at the drain D when turned on. By setting the charge pump 240, a boost operation can be achieved to obtain a potential V higher than the drain D. REF4 The reference potential V REF1 and provides it to the driving device 200, thereby ensuring that the gate potential V G It is sufficient to turn on the power switch device 110 .

[0032] In some embodiments of the present disclosure, the power switch device 110 is adapted to be coupled between a power supply potential and a load 120, and the reference potential V REF4 is the power supply potential, and the reference potential V REF2is the ground potential. Specifically, the power switch device 110 may be a high-side switch, which is coupled between the power supply potential and the load 120 to provide a load current to the load 120. Since the high-side switch is located at the power supply end, in order to ensure that it can be turned on, the gate potential of the power switch device needs to be higher than the power supply potential. The charge pump 240 can raise the power supply potential to a higher potential to provide it to the driving device 200, so that the driving device 200 can drive the power switch device 110 as a high-side switch. In one embodiment, the reference potential V REF3 Specifically, when the power switch device 110 is a high-side switch, the gate potential V of the power switch device 110 when it is turned on is G is approximately equal to the boost potential provided by the charge pump 240, and the gate potential V G Usually higher than the power supply potential. Therefore, the power supply potential can be used as the reference potential V REF3 The discharge path of the first auxiliary driving circuit is constructed so that the additional discharge path discharges from the gate to the power supply potential in the first transition phase S1' of the shutdown. G The power supply potential is usually lower than the power supply potential, so the additional discharge path from the gate to the power supply potential will no longer continue to discharge in the subsequent stage, and the subsequent discharge process is only controlled by the main drive circuit 210. In this way, the power supply potential is cleverly used to determine whether the shutdown process is in the first transition stage S1' or in the subsequent transition stage, thereby simply and effectively realizing the independent adjustment of the first transition stage S1' of the shutdown by the first auxiliary drive circuit 220. Alternatively, the reference potential V REF3 It can be other power rail potentials generated based on the power supply potential. That is, the reference potential V coupled to the first auxiliary driving circuit 220 REF3 It can also be other power rail potentials in the power transmission device 10, for example, a power rail potential 5V lower than the power supply voltage. In this case, depending on the actual reference potential V REF3 The discharge period of the first auxiliary driving circuit 220 may become longer or shorter within a certain range depending on the level of the switching voltage. Although the shorter or longer discharge period may not be enough to cover the initial transition stage or the covered stage has exceeded the initial transition stage, this configuration is also beneficial to shorten the dwell time of the initial transition stage of the shutdown, thereby helping to improve the switching loss, switching response speed, maximum operating frequency and duty cycle difference.

[0033] Figure 5 FIG. 2 shows a schematic circuit diagram of a power transmission device 10 according to another embodiment of the present disclosure. Figure 4 The difference is that Figure 5An exemplary implementation of the first auxiliary driving circuit 220 and the second auxiliary driving circuit 230 of the driving circuit 200 is shown in more detail.

[0034] like Figure 5 As shown, in some embodiments of the present disclosure, the first auxiliary driving circuit 220 includes a first switch branch 221 and a first control branch 222. The first switch branch 221 includes a first control branch 222 coupled in series between the gate G and the reference potential V REF3 The unidirectional conductive device D1 and the first switch tube M1 are connected between the first control branch 222 and the first switch tube M1. The first control branch 222 controls the first switch tube M1 to turn on based on the OFF signal for turning off the power switch device. The first control branch 222 can receive the OFF signal to generate current and voltage, and thus trigger the first switch tube M1 to turn on. For example, the first switch tube M1 can be an N-type MOSFET. In some embodiments, the first control branch 222 includes a series connection to the reference potential V REF1 With reference potential V REF3 The node between the first component E1 and the second component E2 is coupled to the control terminal of the first switch tube M1, wherein the first component E1 includes at least one of a current source and a resistor, and the second component E2 includes at least one of a resistor and / or a diode-connected MOSFET. Specifically, the first switch element SW3 can be controlled by an OFF signal and closed in response to receiving the OFF signal. As a result, the current is switched from the reference potential V REF1 Flows to V through the first component E1 and the second component E2 REF3 , so that a voltage sufficient to turn on the first switch tube M1 is applied between the gate and source. After the first switch tube M1 is turned on, a voltage flows from the gate G to the reference potential V REF3 The discharge current. As the gate potential V G From the output potential V of the charge pump 240 REF1 The potential gradually decreases to the reference potential V REF3 In the following, the unidirectional conduction device D1 is reversely cut off, so that the first switch branch 221 discharges only in the initial transition stage of the shutdown and stops discharging in the subsequent transition stage. As an example, the unidirectional conduction device D1 can be a diode. Alternatively, the unidirectional conduction device D1 can also be other elements that achieve unidirectional conduction, such as a parasitic diode of a MOSFET or a diode-connected MOSFET. In addition, by adjusting the current of the current source or the resistance of the resistor used as the first component E1, adjusting the resistance of the resistor used as the second component E2, and / or adjusting the size of the first switch tube M1, the charge discharge rate of the first switch branch 221 can be adjusted and controlled, thereby achieving more accurate control of the discharge duration.

[0035] In some embodiments of the present disclosure, the first switch branch 221 further includes a resistor R1 coupled in series with the unidirectional conductive device D1 and the first switch tube M1. The number of the resistor R1 can be one or more, and can be set between the gate G and the unidirectional conductive device D1, between the unidirectional conductive device D1 and the first switch tube M1, and / or between the first switch tube M1 and the reference potential V REF3 In addition, the number or resistance value of the resistor R1 can be changed or adjusted. By setting the resistor R1, it is possible to help adjust the rate at which the first switch branch 221 discharges the charge to the gate G, thereby achieving control over the duration of the initial transition phase (eg, the first transition phase S1').

[0036] In some embodiments of the present disclosure, the second auxiliary driving circuit 230 includes a second switch branch 231, a second control branch 232, and a potential monitoring branch 233. The second switch branch 231 includes a second control branch 232 coupled to a reference potential V REF1 The second switch tube M2 between the gate G. The potential monitoring branch 233 is coupled to the reference potential V REF1 and the gate G, and starts and maintains the monitoring gate potential V based on the ON signal for turning on the power switch device 110 G The second control branch 232 is coupled to the reference potential V REF1 With reference potential V REF2 , and based on the potential monitored by the potential monitoring branch 233 exceeding the predetermined threshold potential, the second switch tube M2 is controlled to be turned on. Alternatively, the reference potential V REF2 , the second control branch 232 can also be coupled to the reference potential V REF1 With reference potential V REF3 between.

[0037] The potential monitoring branch 233 can start and maintain monitoring when receiving the ON signal, and use the reference potential V REF1 As a reference, the change of gate potential is estimated, so that the rise of gate potential can be monitored during the turn-on process of the power switch device 110. G When the potential rises to a level exceeding a predetermined threshold potential, the potential monitoring branch 233 can notify or influence the second control branch 232, so that the second control branch 232 controls the second switch tube M2 in the second switch branch 231 to turn on, thereby utilizing the second switch branch 231 at the reference potential V REF1 A charging current path is formed between the gate G and the gate potential V GExceeding the predetermined threshold potential indicates that the power switch device 110 has entered a later transition phase (e.g., the third transition phase S3 of the switch-on process) during the switch-on process. In this way, the charging function of the second switch branch 231 can be enabled in the later transition phase, while avoiding enabling the charging function of the second switch branch 231 before the transition phase.

[0038] In some embodiments of the present disclosure, the potential monitoring branch 233 includes a second switch element SW4 and voltage-dividing resistors R2 and R3 coupled in series, and the second switch element SW4 is turned on based on the ON signal for turning on the power switch device 110. The number of voltage-dividing resistors can be more than two, for example, three or four, and the resistance value of each voltage-dividing resistor can be set according to a predetermined threshold potential. Specifically, during the turn-on process, the gate potential V G The voltage on the voltage-dividing resistor will gradually increase, thereby causing the voltage on the voltage-dividing resistor to decrease. The gate potential can be monitored and determined by the voltage change on the voltage-dividing resistor, and thus the transition stage of switching on can be determined. In some embodiments of the present disclosure, the second control branch 232 includes a third switch tube M3, a third component E3 and a third switch element SW5 coupled in series, and the third switch tube M3 is coupled to the reference potential V REF1 The second switch tube M2 is turned on based on the potential monitored by the potential monitoring branch 233 and the control terminal of the second switch tube M2. The third component E3 includes at least one of a current source and a resistor, and the third switch element SW5 is turned on based on the ON signal. Specifically, the third switch tube M3 in the second control branch 232 can be controlled by the potential monitoring branch 233, and the conduction state of the third switch tube M3 is changed when it is detected that the gate potential exceeds the predetermined threshold, thereby affecting and changing the control terminal potential of the second switch tube M2, so that the second switch tube M2 is switched from the off state to the on state. In one embodiment, the second switch element SW4 and the voltage dividing resistor R3 are coupled between the control terminal of the third switch tube M3 and the gate G, and the voltage dividing resistor R2 is coupled to the reference potential V REF1 For example, the second switch tube M2 and the third switch tube M3 may be P-type MOSFETs, and the gate-source voltage of the third switch tube M3 applied to the P-type MOSFET is changed by using the voltage drop variation degree across the voltage-dividing resistor R2, thereby changing the conduction state of the third switch tube M3, and further controlling the conduction state of the second switch tube M2.

[0039] As an example, after receiving the ON signal, the second switch element SW4 and the third switch element SW5 are both turned on. REF1 and gate potential V G The voltage between is applied to the voltage divider resistors R2 and R3. At the beginning of the turn-on process, the gate potential VG Far below the reference potential V REF1 , so a high voltage drop is generated across the voltage-dividing resistor R2. The high voltage drop across the voltage-dividing resistor R2 causes the third switch tube M3 to be turned on, so that the control terminal of the second switch tube M2 is pulled up to the reference potential V REF1 , causing the second switch tube M2 to be turned off. As the charging process continues, the gate potential V G Rising, reference potential V REF1 and gate potential V G The voltage between the two gates gradually decreases, and thus the voltage drop across the voltage-dividing resistor R2 also gradually decreases. G When the voltage rises above the predetermined threshold potential, the voltage drop across the voltage-dividing resistor R2 drops below the conduction threshold of the third switch tube M3, causing the third switch tube M3 to be turned off. As the third switch tube M3 is turned off, the potential of the control terminal of the second switch tube M2 is pulled down, causing the second switch tube M2 to be turned on. Then, in the later transition stage (e.g., the third transition stage S3) of the turn-on, the second switch branch 231 is used to switch the reference potential V REF1 An additional charging path is formed between the gate G. In one embodiment, the second control branch 232 also includes a circuit coupled to the reference potential V REF1 and a resistor R4 between the control end of the second switch tube M2 and the control end of the second switch tube M2. By setting the resistor R4, the control end of the second switch tube M2 can be prevented from being in a suspended state, thereby reducing the risk of overvoltage damage to the switch tube. In addition, the setting of the resistor R4 can also ensure that the switch tube M2 in the initial state is in an off state and will not be misconnected. Alternatively, the resistor R4 can also be removed from the second control branch 232. In addition, by adjusting the resistance values ​​of the resistors R2, R3 and R4, adjusting the sizes of the second switch tube M2 and the third switch tube M3, and / or adjusting the current or resistance of the resistor used as the current source of the third component E3, the charging start time and charging rate of the second switch branch 231 can be adjusted and controlled, so that the duration of the later transition stage such as the third transition stage S3 can be accurately controlled.

[0040] In some embodiments of the present disclosure, the second switch branch 231 further includes a resistor R5 coupled in series with the second switch tube M2. The number of the resistor R5 can be one or more, and can be set at the reference potential V as needed. REF1 and the second switch tube M2 and / or between the second switch tube M2 and the gate G. In addition, the number or resistance value of the resistor R5 can be changed or adjusted. By setting the resistor R5, it can help adjust the rate at which the second switch branch 231 charges the gate G, thereby achieving more accurate control of the duration of the later transition stage (e.g., the third transition stage S3) of the on-state.

[0041] It is understandable that although Figure 4 and Figure 5 The driving device 200 in the embodiment includes both the first auxiliary driving circuit 220 and the second auxiliary driving circuit 230, but the first auxiliary driving circuit 220 may be removed while the second auxiliary driving circuit 230 is retained, or the second auxiliary driving circuit 230 may be removed while the first auxiliary driving circuit 220 is retained. For example, in the case where the first auxiliary driving circuit 220 is removed while the second auxiliary driving circuit 230 is retained, the driving device 200 may use the second auxiliary driving circuit 230 to add an additional charging path in the later transition stage (e.g., the third transition stage S3) of the switch-on process without adding an additional discharging path in the switch-off process, thereby only controlling the duration of the later transition stage (e.g., the third transition stage S3) of the switch-on process, which may also achieve beneficial effects such as reducing switching losses and improving switching response speed.

[0042] In an embodiment of the present disclosure, by setting at least one of the first auxiliary drive circuit and the second auxiliary drive circuit, the duration of at least one of the initial transition phase of shutdown and the later transition phase of connection can be shortened and controlled, which can effectively improve switching loss and response speed, and help reduce duty cycle errors, thereby improving the performance of the power switching device and the power transmission equipment or system including the power switching device.

[0043] Through the teachings given in the above description and the related drawings, many modifications and other embodiments of the present disclosure given here will be recognized by those skilled in the art of the present disclosure. Therefore, it is to be understood that the embodiments of the present disclosure are not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included in the scope of the present disclosure. In addition, although the above description and the related drawings describe the example embodiments in the context of some example combinations of parts and / or functions, it should be appreciated that different combinations of parts and / or functions can be provided by alternative embodiments without departing from the scope of the present disclosure. In this regard, for example, other combinations of parts and / or functions that are different from those clearly described above are also expected to be within the scope of the present disclosure. Although specific terms are used here, they are only used in a general and descriptive sense and are not intended to be limited.

Claims

1. A driving device (200), comprising: The main driving circuit (210) is coupled to a first reference potential (V REF1 ) and the second reference potential (V REF2 ) and is configured to form a voltage from the first reference potential (V REF1 ) to the gate (G) of the power switch device (110), and based on a second signal for turning off the power switch device (110), a current path from the gate (G) to the second reference potential (V REF2 ) current path, the second reference potential (V REF2 ) is lower than the first reference potential (V REF1 ); as well as A first auxiliary driving circuit (220) is coupled between the gate (G) and a third reference potential (V REF3 ), and is configured to be based on the second signal and based on the potential of the gate (G) being higher than the third reference potential (V REF3 ) to form a voltage from the gate (G) to the third reference potential (V REF3 ) current path, the third reference potential (V REF3 ) is lower than the first reference potential (V REF1 ) and is higher than the second reference potential (V REF2 ).

2. The driving device (200) according to claim 1, further comprising: The second auxiliary driving circuit (230) is coupled to the first reference potential (V REF1 ) and the gate (G), and is configured to form a voltage from the first reference potential (V REF1 ) to the gate (G), the threshold potential is lower than the first reference potential (V REF1 ) and is higher than the second reference potential (V REF2 ).

3. The driving device (200) according to claim 1 or 2, further comprising: A charge pump (240) is coupled to a first reference potential (V REF1 ) is lower than the first reference potential (V REF1 ) of the fourth reference potential (V REF4 ), the drain (D) of the power switch device (110) is suitable for coupling to the fourth reference potential (V REF4 ), The power switch device (110) is suitable for coupling between the power supply potential and the load, and the fourth reference potential (V REF4 ) is the power supply potential, and the second reference potential (V REF2 ) is the ground potential, The third reference potential (V REF3 ) is the power supply potential, or the third reference potential (V REF3 ) are other power rail potentials generated based on the power supply potential.

4. The driving device (200) according to claim 1 or 2, wherein the first auxiliary driving circuit (220) comprises: The first switch branch (221) includes a switch connected in series between the gate (G) and the third reference potential (V REF3 ) between a unidirectional conductive device (D1) and a first switch tube (M1); and The first control branch (222) is configured to control the first switch tube (M1) to turn on based on the second signal.

5. The driving device (200) according to claim 4, wherein the first control branch (222) comprises a first reference potential (V REF1 ) and the third reference potential (V REF3 ), a first switch element (SW3) between the first component (E1) and the second component (E2), a node between the first component (E1) and the second component (E2) is coupled to a control terminal of the first switch tube (M1), and The first switch element (SW3) is configured to be turned on based on the second signal, the first component (E1) includes a current source and / or a resistor, and the second component (E2) includes a resistor and / or a diode-connected metal oxide semiconductor field effect transistor.

6. The driving device (200) according to claim 4, wherein the first switch branch (221) further comprises at least one resistor (R1) coupled in series with the unidirectional conductive device (D1) and the first switch tube (M1).

7. The driving device (200) according to claim 4, wherein the unidirectional conductive device (D1) comprises a diode device or a parasitic diode of a metal oxide semiconductor field effect transistor.

8. The driving device (200) according to claim 2, wherein the second auxiliary driving circuit (230) comprises: The second switch branch (231) includes a switch coupled to the first reference potential (V REF1 ) and the gate (G); Potential monitoring branch (233), coupled to the first reference potential (V REF1 ) and the gate (G), and is configured to monitor the potential of the gate (G) based on the first signal; as well as The second control branch (232) is coupled to the first reference potential (V REF1 ) and the second reference potential (V REF2 ) or the third reference potential (V REF3 ), and is configured to control the second switch tube (M2) to be turned on based on the potential monitored by the potential monitoring branch (233) exceeding the threshold potential.

9. The driving device (200) according to claim 8, wherein the potential monitoring branch (233) comprises a second switch element (SW4) and a plurality of voltage dividing resistors (R2, R3) coupled in series, the second switch element (SW4) being configured to be turned on based on the first signal, and The second control branch (232) comprises a third switch tube (M3), a third component (E3) and a third switch element (SW5) coupled in series, wherein the third switch tube (M3) is coupled to the first reference potential (V REF1 ) and the control end of the second switch tube (M2) and is configured to turn on the second switch tube (M2) based on the potential monitored by the potential monitoring branch (233) exceeding the threshold potential, the third component (E3) includes a current source and / or a resistor, and the third switch element (SW5) is configured to be turned on based on the first signal.

10. The driving device (200) according to claim 9, wherein the second control branch (232) further comprises a first reference potential (V REF1 ) and a resistor (R4) between the control end of the second switch tube (M2).

11. The driving device (200) according to claim 9, wherein the second switch element (SW4) and at least one of the plurality of voltage-dividing resistors (R2, R3) are coupled between the control terminal of the third switch tube (M3) and the gate (G), and the other voltage-dividing resistors (R2, R3) are coupled to the first reference potential (V REF1 ) and the control end of the third switch tube (M3).

12. The driving device (200) according to claim 8, wherein the second switch branch (231) further comprises at least one resistor (R5) coupled in series with the second switch tube (M2).

13. The driving device (200) according to claim 2, wherein the threshold potential indicates the beginning of the transition phase of the power switch device (110) from the saturation region to the deep linear region, and the third reference potential (V REF3 ) indicates the end of the transition phase of the power switch device (110) from the linear region to the saturation region.

14. A driving device (200), comprising: The main driving circuit (210) is coupled to a first reference potential (V REF1 ) and the second reference potential (V REF2 ) and is configured to form a voltage from the first reference potential (V REF1 ) to the gate (G) of the power switch device (110), and based on a second signal for turning off the power switch device (110), a current path from the gate (G) to the second reference potential (V REF2 ) current path, the second reference potential (V REF2 ) is lower than the first reference potential (V REF1 ); as well as The second auxiliary driving circuit (230) is configured to generate a gate potential (V REF1 ) to the gate (G), the threshold potential is lower than the first reference potential (V REF1 ) and is higher than the second reference potential (V REF2 ), the second auxiliary driving circuit (230) comprises: The second switch branch (231) includes a switch coupled to the first reference potential (V REF1 ) and the gate (G); Potential monitoring branch (233), coupled to the first reference potential (V REF1 ) and the gate (G), and is configured to monitor the potential of the gate (G) based on the first signal; The second control branch (232) is coupled to the first reference potential (V REF1 ) and the second reference potential (V REF2 ) or the third reference potential (V REF3 ), and is configured to control the second switch tube (M2) to be turned on based on the potential monitored by the potential monitoring branch (233) exceeding the threshold potential.

15. The driving device (200) according to claim 14, wherein the potential monitoring branch (233) comprises a second switch element (SW4) and a plurality of voltage dividing resistors (R2, R3) coupled in series, the second switch element (SW4) being configured to be turned on based on the first signal, and The second control branch (232) comprises a third switch tube (M3), a third component (E3) and a third switch element (SW5) coupled in series, wherein the third switch tube (M3) is coupled to the first reference potential (V REF1 ) and the control end of the second switch tube (M2) and is configured to turn on the second switch tube (M2) based on the potential monitored by the potential monitoring branch (233) exceeding the threshold potential, and the third component (E3) includes a current source and / or a resistor, and the third switch element (SW5) is configured to be turned on based on the first signal.

16. The driving device (200) according to claim 15, wherein the second control branch (232) further comprises a first reference potential (V REF1 ) and a resistor (R4) between the control end of the second switch tube (M2).

17. The driving device (200) according to claim 15, wherein the second switch element (SW4) and at least one of the plurality of voltage-dividing resistors (R2, R3) are coupled between the control terminal of the third switch tube (M3) and the gate (G), and the other voltage-dividing resistors (R2, R3) are coupled to the first reference potential (V REF1 ) and the control end of the third switch tube (M3).

18. The driving device (200) according to claim 14, wherein the second switch branch (231) further comprises at least one resistor (R5) coupled in series with the second switch tube (M2).

19. A power transmission device (10), comprising: A power switching device (110); as well as The driving device (200) according to any one of claims 1 to 18, coupled to a gate (G) of the power switching device (110).

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