Driving apparatus and power transmission device

Abstract

Provided in the embodiments of the present disclosure are a driving apparatus and a power transmission device. The driving apparatus comprises: a main driving circuit, which is coupled between a first reference potential and a second reference potential, and is configured to form a current path from the first reference potential to a gate electrode of a power switching device on the basis of a first signal for turning on the power switching device, and to form a current path from the gate electrode to the second reference potential on the basis of a second signal for turning off the power switching device, wherein the second reference potential is lower than the first reference potential; and a first auxiliary driving circuit, which is coupled between the gate electrode and a third reference potential, and is configured to form a current path from the gate electrode to the third reference potential on the basis of the second signal and on the basis that the potential of the gate electrode is higher than the third reference potential, wherein the third reference potential is lower than the first reference potential and higher than the second reference potential. By means of the embodiments of the present disclosure, various performance aspects of a power switching device, such as the switching loss and the response speed, can be effectively improved.

Description

Drive unit and power transmission equipment

[0001] This invention claims priority to Chinese Patent Application No. 202411919500.5, filed with the Chinese Patent Office on December 24, 2024, entitled “Driver and Power Transmission Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to power electronics technology, and more specifically, to a drive device for power switching devices and a power transmission device including the drive device. Background Technology

[0003] Power switching devices typically require a pre-stage driver circuit to drive and control their on / off states. In some applications (such as automotive high-side switches), power switching devices need to drive inductive or resistive loads. To prevent overshoot and damage to the switch itself or subsequent circuitry due to overvoltage, the driver circuit of the power switching device needs to implement soft-start and / or soft-turn-off functions. Furthermore, to ensure the switch has a high operating frequency and low switching losses in certain modes (such as PWM control mode), the turn-on and / or turn-off rates of the driver circuit cannot be too slow. In other words, the driver circuit needs to have a certain control capability for turn-on and / or turn-off rates.

[0004] However, due to the different characteristics of the various transition stages during the switching process, current drive schemes struggle to achieve precise rate control. The excessively long dwell time of power switching devices during some transition stages increases switching losses and affects switching response time. Summary of the Invention

[0005] To at least partially address the above and other potential problems, embodiments of this disclosure provide a drive device and a power transmission device including the drive device.

[0006] According to a first aspect of this 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 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 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.

[0007] According to a second aspect of this 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 a gate potential 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 includes: a second switching branch including a second switching transistor 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; and a second control branch coupled between the first reference potential and either the second or third reference potential, and configured to control the second switching transistor to turn on based on a potential monitored by the potential monitoring branch exceeding the threshold potential.

[0008] According to a third aspect of this disclosure, a power transmission device is provided. The power transmission device includes: a power switching device; and a driving means according to the first or second aspect, coupled to the gate of the power switching device.

[0009] The summary section is provided to present the chosen concepts in a simplified form, which will be further described in the detailed description below. The summary section is not intended to identify key or principal features of this disclosure, nor is it intended to limit the scope of this disclosure. Attached Figure Description

[0010] The above and other objects, features and advantages of this disclosure will become more apparent from the accompanying drawings, in which like reference numerals generally denote like parts.

[0011] Figure 1 shows a schematic circuit diagram of a power transmission device.

[0012] Figure 2 shows the waveforms of the gate potential, output potential, turn-on control signal, and turn-off control signal during the operation of the power switching device.

[0013] Figure 3 shows a schematic circuit diagram of a power transmission device according to an embodiment of the present disclosure.

[0014] Figure 4 shows a schematic circuit diagram of a power transmission device according to an embodiment of the present disclosure.

[0015] Figure 5 shows a schematic circuit diagram of a power transmission device according to an embodiment of the present disclosure. Detailed Implementation

[0016] Embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. Those skilled in the art can derive alternative technical solutions from the following description without departing from the spirit and scope of the present disclosure.

[0017] The term “comprising” and its variations as used herein signify open inclusion, i.e., “including but not limited to”. Unless otherwise stated, the term “or” means “and / or”. The term “based on” means “at least partially based on”. The term “an embodiment” means “at least one example embodiment”. Other explicit and implicit definitions may also be included below.

[0018] Figure 1 shows a schematic circuit diagram of the power transmission device 10'. As shown in Figure 1, the power transmission device 10' includes a power switching device 110' and a load 120', which are connected in series between the power supply potential and the ground potential. The power transmission device 10' also includes a drive circuit 200' connected to the gate of the power switching device 110' to drive the power switching device 110', thereby realizing the turn-on and turn-off operations of the power switching device 110'. The drain D' of the power switching device 110' is connected to the power supply potential, and the source S' of the power switching 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 Furthermore, the power switching device 110' has a parasitic capacitance C between its gate G' and drain D'. gd It has a parasitic capacitance C between its gate G' and source S'. gs '.

[0019] The drive circuit 200' can provide turn-on rate and / or turn-off rate control functions. Specifically, the drive 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 switching device 110', switch SW1' can be closed under the control of a turn-on signal, and the drive circuit 200' uses the current from current source I1' to control the parasitic capacitance C of the power switching device 110'. gd 'and C gsCharging is performed to switch the power switching device 110 from the off state to the on state. The parasitic capacitance C can be changed by setting or adjusting the current of the current source I1'. gd 'and C gs The charging rate of the power switching device 110' is controlled to control the turn-on rate of the power switching device 110'. During the turn-off process of the power switching device 110', the switch SW2' can be closed under the control of the turn-off signal, and the drive circuit 200' uses the current from the current source I2' to control the parasitic capacitance C of the power switching device 110'. gd 'and C gs Discharge causes the power switching device 110 to switch from the on state to the off state. The parasitic capacitance C can be changed by setting or adjusting the current of the current source I2'. gd 'and C gs The discharge rate of the power switching device 110 is controlled to control the turn-off rate of the power switching device 110.

[0020] Figure 2 shows the gate potential V during the operation of the power switching device 110'. G Output potential V OUT 'Connect control signal G' ON and the shutdown control signal G OFF The waveform diagram is shown below. As an example, load 120' is a resistive load. The turn-on process of power switching device 110' can be divided into three transition stages S1, S2 and S3, and the turn-off process of power switching device 110' can also be divided into three transition stages S1', S2' and S3'.

[0021] In the first transition phase S1 of the switching process, switch SW1' is closed (switch SW2' is open), so that the current source I1' provides a constant current to the gate-source parasitic capacitance C of the power switching device 110'. gs 'and gate-drain parasitic capacitance C gd During the charging process, the power switching device 110 transitions from the cutoff region to the saturation region. In the second transition phase S2 of the switching process, the current source I1' operates with a constant current as the gate-drain parasitic capacitance C. gd Charging continues until the power switch 110' enters the linear region, at which point the source potential of the power switch 110' is close to the drain potential. In the third transition stage S3 of the switching process, the constant current from the constant current source I1' continues to be equal to the gate-source parasitic capacitance C. gs 'and gate-drain parasitic capacitance C gdThe power switching device 110 is charged until it is fully turned on and enters the deep linear region. During the first transition phase S1', second transition phase S2', and third transition phase S3' of the turn-off process, switch SW2' is closed (switch SW1' is open), and the constant current from constant current source I2' discharges the parasitic capacitance, thus causing the power switching device 110' to transition from fully on to fully off with the opposite state change. The principle and state changes of the turn-off process are similar to those of the turn-on process, and therefore will not be described further.

[0022] Because the characteristics of each transition stage differ, it is difficult to achieve precise turn-on rate control and / or turn-off rate control using a single current source. Furthermore, the gate-source parasitic capacitance C of the power switching device... gs Typically, the gate-source voltage V of the power switching device is relatively large, especially during the first transition phase S1 of turn-off and the third transition phase S3 of turn-on. gs Significant variations will occur, leading to longer dwell times in these two phases. This increases switching losses during the turn-on and turn-off processes and affects the switching response time. In some control modes, such as PWM, the maximum operating frequency of the switch will be affected and limited. Furthermore, for both turn-on and turn-off, the switching states differ during the transition from the control signal to the output signal, causing the actual turn-on delay to differ from the actual turn-off delay. This creates asymmetry in the turn-on and turn-off processes, resulting in duty cycle errors. Excessive dwell time in partial transition phases (such as the third stage of turn-on and the first stage of turn-off) will amplify this duty cycle error.

[0023] Embodiments of this disclosure provide an improved driving scheme for power switching devices. In the improved scheme, in addition to the main driving circuit, a first auxiliary driving circuit is added and coupled between the gate of the power switching device and a third reference potential, which is lower than the first reference potential and higher than the second reference potential. This adds an additional discharge path during the initial transition phase of turn-off, accelerating the discharge process and preventing the switch from remaining in the initial transition phase for too long during turn-off. Since the additional discharge path is coupled between the gate of the power switching device and the third reference potential, the additional discharge path automatically stops discharging during subsequent transition phases when the gate potential is lower. This ensures, in a simple and effective manner, that the first auxiliary driving circuit operates only during the slow initial transition phase without affecting later transition phases. By incorporating the first auxiliary driving circuit, the initial transition phase during turn-off can be accelerated and shortened, which helps reduce switching losses, improve the response speed during switch turn-off, increase the switching operating frequency, and achieve more precise turn-off rate control. In some embodiments of this disclosure, a second auxiliary drive circuit is also provided. This second auxiliary drive circuit can introduce an additional charging path in the later transition phase of the turn-on process of the power switching device, thereby accelerating the charging process in the later transition phase, shortening the dwell time in this phase, and thus helping to reduce switching losses, improve the response speed when the switch is turned on, provide the switching operating frequency, and achieve more precise turn-on rate control. Furthermore, by shortening the initial transition phase of the turn-off process and / or the later transition phase of the turn-on process, it helps to reduce or eliminate the asymmetry of the turn-on and turn-off processes, thereby reducing or eliminating duty cycle errors.

[0024] Figure 3 shows a schematic circuit diagram of a power transmission device 10 according to an embodiment of the present disclosure. As shown in Figure 3, the power transmission device 10 includes a power switching device 110 and a load 120. As an example, the power switching device 110 may be an N-type metal-oxide-semiconductor field-effect transistor (MOSFET), and the load 120 may be a resistive and / or inductive load. However, it will be understood that the power switching device 110 may be other suitable types of power switching devices, and the load 120 may be other types of loads. The power switching device 110 and the load 120 are coupled in series at a reference potential V. REF4 With reference potential V REF2 Between. For example, the reference potential V. REF4 It can be the power supply potential, and the reference potential V. REF2 It can be ground potential. The power switching device 110 has a gate (G), drain (D), source (S), and gate-source parasitic capacitance (C). gs and gate-drain parasitic capacitance Cgd 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 load 120. In addition, the power transmission device 10 also includes a drive unit 200. The drive unit 200 is coupled to the gate G of the power switching device 110 and is used to drive the power switching device 110 to turn it on and off.

[0025] The drive unit 200 includes a main drive circuit 210. The main drive circuit 210 is coupled to a reference potential V. REF1 With reference potential V REF2 Between, and based on the signal used to turn on the power switching device 110, a value is formed from the reference potential V. REF1 A current path is formed from the gate G of the power switching device 110, and a path from the gate G to the reference potential V is formed based on the signal used to turn off the power switching device 110. REF2 The current path, in which the reference potential V REF2 Below the reference potential V REF1 As an example, the reference potential V REF2 It is the ground potential, and the reference potential V REF1 This is the boost potential output by the charge pump. The main drive circuit 210 may include switching elements SW1 and SW2 and current sources I1 and I2, with switching element SW1 and current source I1 connected in series at the reference potential V. REF1 Between the gate G of the power switching device 110 and the current source I2 and the switching element SW2, the gate G and the reference potential V are coupled in series. REF2 Between. When the controller (not shown) of the power transmission device 10 or the power switching device 110 sends an on or off control signal (e.g., the high-level active signal G in Figure 2) to the drive device 200 to turn the power switching device 110 on or off. ON or signal G OFF When the main drive circuit 210 performs corresponding operations to drive the power switching device 110, specifically, when an ON control signal (hereinafter referred to as the ON signal) is sent to the drive device 200 to turn on the power switching device 110, the switching element SW1 will be closed under the control of the ON signal, and the switching element SW2 will remain open, thereby allowing the constant current of the current source I1 to flow from the reference potential V. REF1 The current flows to the gate G and to the parasitic capacitance C of the power switching device 110. gs and C gsCharging is performed. When a turn-off control signal (hereinafter referred to as the OFF signal) is sent to the drive device 200 to turn off the power switching device 110, the switching element SW2 will be closed under the control of the OFF signal, and the switching element SW1 will remain open, thereby allowing the constant current of the current source I2 to flow from the gate G to the reference potential V. REF2 And for the parasitic capacitance C of the power switching device 110 gs and C gs Discharge occurs. The charging rate during the turn-on process and the discharging rate during the turn-off process can be adjusted by setting the currents of current sources I1 and I2. 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. The charging rate during the turn-on process and the discharging rate during the turn-off process can also be adjusted by setting the resistance of the resistor or by setting both the resistance of the resistor and the current of the current source.

[0026] The drive device 200 also includes a first auxiliary drive circuit 220. The first auxiliary drive circuit 220 is coupled to the gate G of the power switching device 110 and the reference potential V. REF3 Between, and based on the OFF signal used to turn off the power switching device 110 and based on the fact that the potential of the gate G is higher than the reference potential V REF3 And form a path from the gate G to the reference potential V REF3 The current path. Reference potential V REF3 Below the reference potential V REF1 And higher than the reference potential V REF2 .

[0027] As an example, the reference potential V REF1 V REF2 and V REF4 These can be potentials higher than the power supply potential (e.g., the boost potential of a charge pump), ground potential, and power supply potential, respectively, with a reference potential V. REF3 It can be the power supply potential or other power rail potentials derived from 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 It is selected or set to indicate the end of the transition phase from the linear region to the saturation region of the power switching device 110. That is, the reference potential V REF3 The potential of the gate G at the end of the first transition phase S1' (see Figure 2) of the turn-off can be close to or equivalent to that of the gate. The output node potential V at the end of the first transition phase S1' of the turn-off is... OUT Based on the potential when the power switching device 110 is fully turned on. V S ILOAD and R on These represent the power supply potential (e.g., reference potential V). REF4 The current of load 120 and the on-resistance of power switching device 110. Furthermore, the potential of gate G at the end of the first transition phase S1' of turn-off can be controlled by V. G =V OUT +V gs To estimate, where V gs V represents the gate-source voltage. gs The voltage (V) can be determined using the current-voltage characteristic curve of the power switching device (e.g., MOSFET) and the load current, for example, by looking up a table, or by using the saturation current formula of the power switching device. G or V gs For example, the saturation current formula for a MOSFET is: , where I d V 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, and V represents the voltage. TH This is the threshold voltage of the MOSFET.

[0028] When the power switching device 110 is in the fully ON state, the potential of the gate G is approximately equal to the reference potential V. REF1 It is higher than the reference potential V. REF3 Furthermore, the OFF signal used to turn off the power switching device 110 can enable the flow from the gate G to the reference potential V in the first auxiliary drive circuit 220. REF3 The discharge path is provided by the main drive circuit 210. Therefore, 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 switching device 110. For example, this additional discharge path can be introduced in the transition phase S1' shown in FIG. 2. That is, during the initial transition phase of the turn-off process, the discharge path provided by the current source I2 of the main drive circuit 210 and the switching element SW2, along with the additional discharge path provided by the first auxiliary drive circuit 220, jointly perform the discharge. This can accelerate the discharge of the parasitic capacitance of the power switching device 110 during the initial transition phase of turn-off, such as transition phase S1', thereby shortening and controlling the duration of the initial transition phase. As the discharge during the turn-off process continues, the potential of the gate G gradually decreases and will fall below the reference potential V. REF3Therefore, the discharge path provided by the first auxiliary drive circuit 220 can automatically stop operating in the later transition phases of the turn-off process (e.g., transition phases S2' and S3'), and only the main drive circuit 210 performs the discharge. This avoids the first auxiliary drive circuit 220 affecting subsequent transition phases. In this way, the duration of the initial transition phase of turn-off can be shortened and controlled, especially the duration of the turn-off transition phase S1' or the time for the power switching device to transition from the linear region to the saturation region during the turn-off process, thereby reducing switching losses, improving switching response speed, and helping to increase the maximum operating frequency of the switch. In addition, shortening the duration of the initial transition phase of turn-off also helps to improve the asymmetry of the turn-on and turn-off processes, thereby reducing duty cycle error.

[0029] Figure 4 shows a schematic circuit diagram of a power transmission device 10 according to another embodiment of the present disclosure. Unlike Figure 3, the drive unit 200 of the power transmission device 10 in Figure 4 further includes a second auxiliary drive circuit 230. The second auxiliary drive circuit 230 is coupled to a reference potential V. REF1 Between the gate G and the reference potential V, 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. REF1 The current path to the gate G. This predetermined threshold potential is lower than the reference potential V. REF1 And higher than the second reference potential V REF2 .

[0030] The predetermined threshold potential can be preset in the second auxiliary drive circuit 230, and can be selected in conjunction with the reference potential V. REF3 Similarly, the predetermined threshold potential can be set to be equal to the power supply potential or equal to another power rail potential generated by the power supply potential. In one embodiment, the predetermined threshold potential can be set to indicate the start of the transition phase from the saturation region to the deep linear region of the power switching device 110. That is, the predetermined threshold potential can be set to be close to or equal to the gate potential V corresponding to the start of the third transition phase S3 (see FIG. 2) of the turn-on. G The gate potential V G It can be determined or calculated in the same way as the gate potential corresponding to the end of the first transition phase S1' of the turn-off described above.

[0031] If the second auxiliary drive circuit 230 receives an ON signal to turn on the power switching device 110, and the potential of the gate G is higher than a predetermined threshold potential set internally in the second auxiliary drive circuit 230, the second auxiliary drive circuit 230 will enable the switching from the reference potential V. REF1A charging path to the gate G. Therefore, in addition to the charging path provided by the main drive circuit 210, an additional charging path can be introduced by the second auxiliary drive circuit 230 during a later transition phase of turning on the power switching device 110. For example, this additional charging path is introduced in transition phase S3 shown in FIG. 2. That is, during a later transition phase of the turn-on process, the charging path provided by the current source I1 of the main drive circuit 210 and the switching element SW1, along with the additional charging path provided by the second auxiliary drive circuit 230, jointly perform charging. This can accelerate the charging of the parasitic capacitance of the power switching device 110 during a later transition phase such as transition phase S3, thereby shortening the duration of the later transition phase. Furthermore, during the initial or early transition phases of the turn-on process (e.g., the first transition phase S1 and the second transition phase S2), the gate G is at a lower potential, below a predetermined threshold potential. Consequently, the additional charging path in the second auxiliary drive circuit 230 is not activated during these initial or early transition phases; instead, the parasitic capacitance of the power switching device 110 is charged only through the main drive circuit 210. This prevents the second auxiliary drive circuit 230 from affecting the initial or early transition phases. In this way, the duration of later transition phases can be shortened and controlled, particularly the duration of the turn-on transition phase S3 or the time it takes for the power switching device to transition from the saturation region to the deep linear region during turn-on, thereby reducing switching losses, improving switching response speed, and contributing to increasing the maximum operating frequency of the switch.

[0032] In some embodiments of this disclosure, the drive unit 200 of the power transmission device 10 further includes a charge pump 240, which is coupled to a reference potential V. REF1 With a potential lower than the reference potential V REF1 Reference potential V REF4 Between. As an example, in some cases, the source S of the power switch 110 is in a suspended state and reaches the potential on the drain D side. Therefore, in order to ensure that the power switch 110 can be turned on, the potential applied to the gate G needs to be 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 Reference potential V REF1 And provide it to the drive unit 200, thereby ensuring the gate potential V G It is sufficient to turn on the power switching device 110.

[0033] In some embodiments of this disclosure, the power switching device 110 is adapted to be coupled between a power supply potential and a load 120, with a reference potential V. REF4 Let V be the power supply potential, and V be the reference potential. REF2The reference potential is ground. Specifically, the power switching device 110 can be a high-side switch, coupled between the power supply potential and the load 120 to provide load current to the load 120. Since the high-side switch is located at the power supply end, the gate potential of the power switching device needs to be higher than the power supply potential to ensure its conduction. The charge pump 240 can boost the power supply potential to a higher potential to provide to the drive device 200, thereby enabling the drive device 200 to drive the power switching device 110 as a high-side switch. In one embodiment, the reference potential V REF3 This refers to the power supply potential. Specifically, when the power switching device 110 is a high-side switch, the gate potential V of the power switching device 110 when it is turned on is... G Approximately equal to the boost potential provided by charge pump 240, and the gate potential V of the first transition phase S1' during turn-off. G It is usually higher than the power supply potential. Therefore, the power supply potential can be used as a reference potential V. REF3 This is used to construct a discharge path for the first auxiliary drive circuit, so that this additional discharge path discharges from the gate to the power supply potential during the first transition phase S1' of the turn-off. This is due to the gate potential V during the second transition phase S2' and the third transition phase S3' of the turn-off. G Typically below the power supply potential, the additional discharge path from the gate to the power supply potential ceases to discharge in subsequent stages, and the subsequent discharge process is controlled only by the main drive circuit 210. In this way, the power supply potential is cleverly used to determine whether the turn-off process is in the first transition stage S1' or a subsequent transition stage, thus simply and effectively realizing the independent adjustment of the first transition stage S1' of the turn-off by the first auxiliary drive circuit 220. Alternatively, the reference potential V... REF3 It can be another power rail potential generated based on the power supply potential. That is, the reference potential V coupled to the first auxiliary drive circuit 220. REF3 It could also be another power rail potential in the power transmission device 10, for example, a power rail potential that is 5V lower than the power supply voltage. In this case, it depends on the actual reference potential V. REF3 Depending on the level of the discharge, the discharge period of the first auxiliary drive circuit 220 may become longer or shorter within a certain range. Although a shorter or longer discharge period may not be sufficient to cover the initial transition phase or may cover a phase that exceeds the initial transition phase, this configuration is still beneficial for shortening the dwell time of the initial transition phase of the turn-off, thereby helping to improve switching losses, switching response speed, maximum operating frequency, and duty cycle difference.

[0034] Figure 5 shows a schematic circuit diagram of a power transmission device 10 according to another embodiment of the present disclosure. Unlike Figure 4, Figure 5 shows in more detail exemplary implementations of the first auxiliary drive circuit 220 and the second auxiliary drive circuit 230 of the drive circuit 200.

[0035] As shown in Figure 5, in some embodiments of this disclosure, the first auxiliary drive circuit 220 includes a first switching branch 221 and a first control branch 222. The first switching branch 221 includes a control branch connected in series with the gate G and the reference potential V. REF3 A unidirectional conducting device D1 and a first switching transistor M1 are connected. A first control branch 222 controls the first switching transistor M1 to turn on based on an OFF signal for turning off the power switching device. The first control branch 222 can receive the OFF signal to generate current and voltage, and thus trigger the first switching transistor M1 to turn on. For example, the first switching transistor M1 can be an N-type MOSFET. In some embodiments, the first control branch 222 includes components series coupled to a reference potential V. REF1 With reference potential V REF3 The first switching element SW3, the first component E1, and the second component E2 are coupled together, with the node between the first component E1 and the second component E2 coupled to the control terminal of the first switching transistor M1. The first component E1 includes at least one of a current source and a resistor, while the second component E2 includes at least one of a resistor and / or a MOSFET with a diode connection. Specifically, the first switching element SW3 can be controlled by an OFF signal and is closed in response to receiving an OFF signal. Thus, current flows from the reference potential V... REF1 Flowing to V via the first component E1 and the second component E2 REF3 This applies a voltage sufficient to turn on the first switch M1 between its gate and source. After the first switch M1 is turned on, a voltage is generated in the first switching branch 221, flowing from the gate G to the reference potential V. REF3 The discharge current. As the gate potential VG decreases from approximately the output potential V of charge pump 240... REF1 The potential gradually decreases to the reference potential V. REF3 Hereinafter, the unidirectional conducting device D1 is reverse-biased, causing the first switching branch 221 to discharge only during the initial transition phase of turn-off and stop discharging during subsequent transition phases. As an example, the unidirectional conducting device D1 can be a diode. Alternatively, the unidirectional conducting device D1 can also be other components that achieve unidirectional conduction, such as a parasitic diode of a MOSFET or a diode-connected MOSFET. Furthermore, by adjusting the current source used as the current source for the first component E1 or the resistance of the resistor, adjusting the resistance used as the resistor for the second component E2, and / or adjusting the dimensions of the first switching transistor M1, the charge discharge rate of the first switching branch 221 can be adjusted and controlled, thereby achieving more precise control over the discharge duration.

[0036] In some embodiments of this disclosure, the first switching branch 221 further includes a resistor R1 series coupled to the unidirectional conducting device D1 and the first switching transistor M1. The number of resistors R1 can be one or more, and they can be disposed as needed between the gate G and the unidirectional conducting device D1, between the unidirectional conducting device D1 and the first switching transistor M1, and / or between the first switching transistor M1 and the reference potential V. REF3 Furthermore, the number or resistance value of resistors R1 can be changed or adjusted. By setting resistors R1, the rate at which the first switching branch 221 discharges charge to the gate G can be adjusted, thereby enabling control over the duration of the initial transition phase (e.g., the first transition phase S1').

[0037] In some embodiments of this disclosure, the second auxiliary drive circuit 230 includes a second switching branch 231, a second control branch 232, and a potential monitoring branch 233. The second switching branch 231 includes a control branch coupled to a reference potential V. REF1 The second switch M2 is connected to the gate G. The potential monitoring branch 233 is coupled to the reference potential V. REF1 The second control branch 232 is coupled to the reference potential VG and is connected to the gate G, and is activated and maintained based on the ON signal used to turn on the power switching device 110. REF1 With reference potential V REF2 Between these points, and based on the potential monitored by the potential monitoring branch 233 exceeding a predetermined threshold potential, the second switch M2 is controlled to turn on. Alternatively, the reference potential V is replaced. REF2 The second control branch 232 can also be coupled to the reference potential V. REF1 With reference potential V REF3 between.

[0038] The potential monitoring branch 233 can start and maintain monitoring upon receiving an ON signal, and uses a reference potential V. REF1 The gate potential change is estimated using a reference, thereby allowing monitoring of the gate potential rise during the turn-on process of the power switching device 110. When the gate potential VG rises above a predetermined threshold potential, the potential monitoring branch 233 can notify or influence the second control branch 232 to control the second switch M2 in the second switching branch 231 to turn on, thereby utilizing the second switching branch 231 at the reference potential VG. REF1A charging current path is formed between the gate and the gate G. When the gate potential VG exceeds a predetermined threshold potential, it indicates that the power switching device 110 has entered a later transition phase during the turn-on process (e.g., the third transition phase S3). In this way, the charging function of the second switching branch 231 can be enabled in the later transition phase, while the charging function of the second switching branch 231 is avoided before the transition phase.

[0039] In some embodiments of this disclosure, the potential monitoring branch 233 includes a second switching element SW4 and voltage divider resistors R2 and R3 coupled in series. The second switching element SW4 is turned on based on an ON signal for turning on the power switching device 110. The number of voltage divider resistors can be more than two, for example, three or four, and the resistance value of each voltage divider resistor can be set according to a predetermined threshold potential. Specifically, during the turn-on process, the gate potential VG gradually increases, causing the voltage across the voltage divider resistors to decrease. The voltage change across the voltage divider resistors can be used to monitor and determine the gate potential, and thus determine the transition phase of the turn-on. In some embodiments of this disclosure, the second control branch 232 includes a third switching transistor M3, a third component E3, and a third switching element SW5 coupled in series. The third switching transistor M3 is coupled to a reference potential VG. REF1 The second switch M2 is turned on when the gate potential monitored by the potential monitoring branch 233 exceeds a predetermined threshold potential. The third component E3 includes at least one of a current source and a resistor, and the third switching element SW5 is turned on based on an ON signal. Specifically, the third switch M3 in the second control branch 232 can be controlled by the potential monitoring branch 233, and when the gate potential is detected to exceed a predetermined threshold, the conduction state of the third switch M3 is changed, thereby affecting and changing the control terminal potential of the second switch M2, so that the second switch M2 switches from an off state to an on state. In one embodiment, the second switching element SW4 and the voltage divider resistor R3 are coupled between the control terminal and the gate G of the third switch M3, and the voltage divider resistor R2 is coupled to the reference potential V. REF1 Between the control terminal of the third switch M3 and the second switch M2 and the third switch M3. For example, the second switch M2 and the third switch M3 can be P-type MOSFETs, and the gate-source voltage of the third switch M3 applied to the P-type MOSFET is changed by the change in the voltage drop across the voltage divider resistor R2, thereby changing the conduction state of the third switch M3 and further controlling the conduction state of the second switch M2.

[0040] As an example, upon receiving the ON signal, both the second switching element SW4 and the third switching element SW5 are turned on. Reference potential V REF1The voltage between the gate potential VG and the reference potential V is applied across the voltage divider resistors R2 and R3. In the initial stage of the switching process, the gate potential VG is much lower than the reference potential V. REF1 Therefore, a high voltage drop is generated across the voltage divider resistor R2. This high voltage drop across R2 causes the third switch M3 to be turned on, pulling the control terminal of the second switch M2 up to the reference potential V. REF1 This causes the second switch M2 to be turned off. As the charging process continues, the gate potential VG rises, and the reference potential V... REF1 The voltage between the gate potential VG and the voltage across the voltage divider resistor R2 gradually decreases, thus the voltage drop across VG also gradually decreases. As the gate potential VG rises above a predetermined threshold potential, the voltage drop across the voltage divider resistor R2 decreases below the turn-on threshold of the third switch M3, causing the third switch M3 to turn off. With the third switch M3 turned off, the potential at the control terminal of the second switch M2 is pulled down, causing the second switch M2 to turn on. Then, in the later transition phase of the turn-on (e.g., the third transition phase S3), the second switch branch 231 is used to maintain the voltage across the reference potential VG. REF1 An additional charging path is formed between the gate G and the control branch. In one embodiment, the second control branch 232 further includes a path coupled to the reference potential V. REF1 A resistor R4 is used between the control terminal of the second switch M2 and the control terminal of the third switch M2. By setting resistor R4, the control terminal of the second switch M2 is prevented from being suspended, thereby reducing the risk of overvoltage damage to the switch. Furthermore, the setting of resistor R4 ensures that the switch M2 is initially off and will not be falsely turned on. Alternatively, resistor R4 can be removed from the second control branch 232. Moreover, by adjusting the resistance values ​​of resistors R2, R3, and R4, adjusting the dimensions of the second switch M2 and the third switch M3, and / or adjusting the current source used as the current source for the third component E3, or adjusting the resistance of the resistor, the charging turn-on time and charging rate of the second switch branch 231 can be adjusted and controlled, thereby enabling precise control of the duration of later transition stages, such as the third transition stage S3.

[0041] In some embodiments of this disclosure, the second switching branch 231 further includes a resistor R5 coupled in series with the second switching transistor M2. The number of resistors R5 can be one or more, and they can be set at the reference potential V as needed. REF1 It is positioned between the second switching transistor M2 and / or between the second switching transistor M2 and the gate G. Furthermore, the number or resistance value of resistors R5 can be changed or adjusted. By setting resistors R5, the charging rate of the second switching branch 231 to the gate G can be adjusted, thereby achieving more precise control over the duration of later transition phases (e.g., the third transition phase S3) of the turn-on.

[0042] It is understood that although the drive device 200 in Figures 4 and 5 includes both the first auxiliary drive circuit 220 and the second auxiliary drive circuit 230, the first auxiliary drive circuit 220 can be removed while the second auxiliary drive circuit 230 is retained, or vice versa. For example, when the first auxiliary drive circuit 220 is removed while the second auxiliary drive circuit 230 is retained, the drive device 200 can utilize the second auxiliary drive circuit 230 to add an additional charging path during the later transition phase of the turn-on (e.g., the third transition phase S3) without adding an additional discharging path during the turn-off process. This allows control to be applied only to the duration of the later transition phase of the turn-on (e.g., the third transition phase S3), which can also achieve beneficial effects such as reducing switching losses and improving switching response speed.

[0043] In embodiments of this disclosure, by providing at least one of a first auxiliary drive circuit and a second auxiliary drive circuit, the duration of at least one of the initial transition phase of turn-off and the later transition phase of turn-on can be shortened and controlled. This can effectively improve switching losses and response speed, and help reduce duty cycle error, thereby improving the performance of the power switching device and the power transmission device or system including the power switching device.

[0044] From the teachings given in the foregoing description and related drawings, many modifications and other embodiments of the present disclosure will become apparent to those skilled in the art. Therefore, it is to be understood that embodiments of the present disclosure are not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of this disclosure. Furthermore, although the foregoing description and related drawings have described exemplary embodiments in the context of certain example combinations of components and / or functions, it should be appreciated that different combinations of components and / or functions may be provided by alternative embodiments without departing from the scope of this disclosure. In this regard, for example, other combinations of components and / or functions that differ from those explicitly described above are also contemplated within the scope of this disclosure. Although specific terms are used herein, they are used in a general and descriptive sense only and are not intended to be limiting.

Claims

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

2. The driving device (200) according to claim 1 further includes: The second auxiliary drive circuit (230) is coupled to the first reference potential (V). REF1 Between the gate (G) and the first reference potential (V), and configured to form a voltage from the first reference potential (V) based on the first signal and based on the potential of the gate (G) being higher than a threshold potential. REF1 A current path to the gate (G) is provided, wherein the threshold potential is lower than the first reference potential (V). REF1 And higher than the second reference potential (V) REF2 ).

3. The driving device (200) according to claim 1 or 2 further includes: A charge pump (240) is coupled to a first reference potential (V). REF1 ) and below the first reference potential (V REF1 The fourth reference potential (V) REF4 Between, the drain (D) of the power switching device (110) is adapted to couple to the fourth reference potential (V). REF4 ), The power switching device (110) is adapted to be coupled 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) is... REF2 ) represents the ground potential. The third reference potential (V) REF3 ) is the power supply potential, or the third reference potential (V) REF3 Other power rail potentials are 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 switching branch (221) includes a series coupling between the gate (G) and the third reference potential (V). REF3 The unidirectional conducting device (D1) and the first switching transistor (M1) between; and The first control branch (222) is configured to control the first switch (M1) to turn on based on the second signal.

5. The drive device (200) according to claim 4, wherein the first control branch (222) comprises a component series coupled to the first reference potential (V). REF1 ) and the third reference potential (V REF3 The first switching element (SW3), the first component (E1), and the second component (E2) are connected, with the node between the first component (E1) and the second component (E2) coupled to the control terminal of the first switching transistor (M1). The first switching 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 metal-oxide-semiconductor field-effect transistor with a resistor and / or a diode connection.

6. The drive device (200) according to claim 4, wherein the first switching branch (221) further includes at least one resistor (R1) coupled in series with the unidirectional conducting device (D1) and the first switching transistor (M1).

7. The driving device (200) according to claim 4, wherein the unidirectional conducting 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 switching branch (231) includes a circuit coupled to the first reference potential (V). REF1 The second switch (M2) between the gate (G) and the gate (G); The potential monitoring branch (233) is coupled to the first reference potential (V). REF1 The potential of the gate (G) is located between the gate (G) and 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 The second switch (M2) is configured to be turned on based on the potential monitored by the potential monitoring branch (233) exceeding the threshold potential.

9. The drive device (200) according to claim 8, wherein the potential monitoring branch (233) includes a second switching element (SW4) coupled in series and a plurality of voltage divider resistors (R2, R3), the second switching element (SW4) being configured to be turned on based on the first signal, and The second control branch (232) includes a third switch (M3), a third component (E3), and a third switching element (SW5) coupled in series. The third switch (M3) is coupled to the first reference potential (V). REF1 The third component (E3) is configured to connect to the control terminal of the second switch (M2) and to turn on the second switch (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 switching element (SW5) is configured to be turned on based on the first signal.

10. The drive device (200) according to claim 9, wherein the second control branch (232) further comprises coupled to the first reference potential (V REF1 The resistor (R4) between the second switch (M2) and the control terminal.

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

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

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

14. A driving device (200), comprising: The main drive circuit (210) is coupled to the first reference potential (V). REF1 ) and the second reference potential (V REF2 Between, and configured to form from the first reference potential (V) based on a first signal for turning on the power switching device (110). REF1 A current path is formed from the gate (G) of the power switching device (110) to the second reference potential (V) based on a second signal for turning off the power switching device (110). REF2 The current path of the second reference potential (V) REF2 ) lower than the first reference potential (V REF1 ); as well as The second auxiliary drive circuit (230) is configured to generate a voltage from the first reference potential (V) based on the first signal and based on the potential of the gate (G) being higher than the threshold potential. REF1 A current path to the gate (G) is provided, wherein the threshold potential is lower than the first reference potential (V). REF1 And higher than the second reference potential (V) REF2 The second auxiliary drive circuit (230) includes: The second switching branch (231) includes a circuit coupled to the first reference potential (V). REF1 The second switch (M2) between the gate (G) and the gate (G); The potential monitoring branch (233) is coupled to the first reference potential (V). REF1 The potential of the gate (G) is located between the gate (G) and 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 The second switch (M2) is configured to be turned on based on the potential monitored by the potential monitoring branch (233) exceeding the threshold potential.

15. The drive device (200) according to claim 14, wherein the potential monitoring branch (233) includes a second switching element (SW4) coupled in series and a plurality of voltage divider resistors (R2, R3), the second switching element (SW4) being configured to be turned on based on the first signal, and The second control branch (232) includes a third switch (M3), a third component (E3), and a third switching element (SW5) coupled in series. The third switch (M3) is coupled to the first reference potential (V). REF1 The third component (E3) is configured to connect to the control terminal of the second switch (M2) and to turn on the second switch (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 switching element (SW5) is configured to be turned on based on the first signal.

16. The drive device (200) according to claim 15, wherein the second control branch (232) further comprises coupled to the first reference potential (V REF1 The resistor (R4) between the second switch (M2) and the control terminal.

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

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

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

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