Gate drive circuit, gate drive device, motor system, vehicle, and current consumption reduction method

Abstract

The invention provides a gate drive circuit, a gate drive device, a motor system, a vehicle, and a current consumption reduction method. A gate drive circuit is configured to drive a gate of a second switching device in a motor drive circuit including a plurality of half-bridge circuits, each half-bridge circuit including a first switching device and a second switching device, and a second switching device connected in series to the first switching device and provided on a low potential side with respect to the first switching device, the motor driving circuit being configured to drive a motor. The gate drive circuit includes: a current source unit configured to allow a current to flow into the gate; and a current sink unit configured to draw a current from the gate electrode. The current source unit includes a first diode disposed in an orientation in which a cathode of the first diode points to a side of the gate where the second switching device is present.

Description

Technical Field

[0001] The present disclosure relates to a gate driving circuit, a gate driving device, a motor system, a vehicle, and a current consumption reduction method. Background Art

[0002] Japanese Patent Application Publication No. 2021-29084 discloses a motor driver that enables power consumption to be suppressed when a short brake is applied to a motor. Figure 8 In the motor driver shown, the control logic unit turns off both the high-side pre-driver and the low-side pre-driver when a short brake is applied to the motor. Summary of the invention

[0003] However, in Japanese Patent Publication No. 2021-29084 Figure 8 There is room for reducing current consumption in the motor drive shown.

[0004] In Japanese Patent Application Publication No. 2021-29084 Figure 8 In the motor driver shown, the control logic unit is in an enabled state when a short brake is applied to the motor, and therefore, an internal power supply circuit that supplies power to the control logic unit causes current consumption when a short brake is applied to the motor.

[0005] In the case of a modified structure in which the analog switch is controlled in response to a brake signal without the intervention of the control logic unit, the control logic unit and the internal power supply circuit can be brought into a disabled state when a short brake is applied to the motor. When the internal power supply circuit is already in a disabled state, the output impedance is in a high impedance state.

[0006] However, even in the case of a modified structure in which the analog switch is controlled in response to the brake signal without intervention of the control logic unit, as long as the analog switch is turned on, current flows from the analog switch to the internal power supply circuit via the body diode of the high-side transistor in the low-side pre-driver. Therefore, current consumption occurs in the internal power supply circuit in the disabled state.

[0007] The gate drive circuit disclosed in this article is configured to drive the gate of the second switching device in the motor drive circuit.

[0008] The motor driving circuit includes a plurality of half-bridge circuits, each of which includes:

[0009] a first switching device, and

[0010] The second switching device,

[0011] The second switching device is connected in series to the first switching device, and

[0012] the second switching device is arranged on a low potential side relative to the first switching device,

[0013] The motor drive circuit is configured to drive the motor,

[0014] The gate drive circuit comprises:

[0015] a current source unit configured to allow current to flow into the gate of the second switching device; and

[0016] a current sink unit configured to draw current from the gate of the second switching device,

[0017] The current source unit includes a first diode disposed in an orientation where a cathode of the first diode points to a side where the gate of the second switching device exists.

[0018] The gate driving device disclosed in this article includes:

[0019] A gate drive circuit having the above structure; and

[0020] A first switching device gate drive circuit is configured to drive a gate of the first switching device.

[0021] The motor system disclosed in this article includes:

[0022] A gate driving device having the above structure;

[0023] the motor drive circuit; and

[0024] The motor.

[0025] The vehicle disclosed herein comprises:

[0026] A motor system having the above structure.

[0027] In the current consumption reduction method disclosed herein,

[0028] The motor drive circuit includes a plurality of half-bridge circuits, each of which includes:

[0029] a first switching device, and

[0030] The second switching device,

[0031] The second switching device is connected in series to the first switching device, and

[0032] the second switching device is arranged on a low potential side relative to the first switching device,

[0033] The motor drive circuit is configured to drive a motor, and

[0034] The current consumption reduction method includes providing a diode in a current source unit, the current source unit being configured to allow current to flow into the gate of the second switching device, and the diode being arranged in an orientation with the cathode of the diode pointing to a side where the gate of the second switching device is present, thereby reducing the current consumption when a short brake is applied to the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram showing a schematic structure of a motor system according to a first embodiment;

[0036] Figure 2 is an external stereogram of a gate drive device;

[0037] Figure 3 is a schematic diagram showing a schematic structure of a motor system according to a second embodiment;

[0038] Figure 4 is a schematic diagram showing a schematic structure of a motor system according to a third embodiment;

[0039] Figure 5 is a schematic diagram showing a schematic structure of a motor system according to a fourth embodiment;

[0040] Figure 6 is a schematic diagram showing an example of the structure of a brake circuit;

[0041] Figure 7 is a schematic diagram showing an example of the structure of a control circuit and a power supply;

[0042] Figure 8 is a view showing the appearance of a vehicle; and

[0043] Fig. 9 is a schematic diagram showing an example of the structure of a power window system to which the motor system is applied. DETAILED DESCRIPTION

[0044] In this article, MOSFET (Metal Oxide Semiconductor Field Effect Transistor) refers to a field effect transistor having a gate structure composed of at least three layers of "a layer formed of a conductor or semiconductor (such as polysilicon) having a small resistance value", "an insulating layer" and "a P-type, N-type or intrinsic semiconductor layer". That is, the gate structure of MOSFET is not limited to a three-layer structure composed of metal, oxide and semiconductor.

[0045] <First Embodiment>

[0046] Figure 1 is a schematic diagram showing a schematic structure of a motor system according to a first embodiment. Figure 1 The shown motor system SYS1 includes an MCU (microcontroller unit) 1 , a gate driving device 2A, a first half-bridge circuit including switching devices M1 and M2 , a second half-bridge circuit including switching devices M3 and M4 , and a motor 3 . Figure 1 The illustrated motor system SYS1 further includes resistors R1 to R5 and switches SW1 and SW2 . The motor drive circuit composed of the gate drive device 2A, the first half-bridge circuit, and the second half-bridge circuit drives the motor 3 .

[0047] In this embodiment, the switching devices M1 to M4 are all N-channel MOSFETs. The switching device M2 is connected in series with the switching device M1 and is disposed on the low potential side relative to the switching device M1. The switching device M4 is connected in series with the switching device M3 and is disposed on the low potential side relative to the switching device M3.

[0048] The MCU 1 supplies a first PWM (Pulse Width Modulation) signal to a terminal PWM1 of the gate driving device 2A, and supplies a second PWM signal to a terminal PWM2 of the gate driving device 2A.

[0049] The gate driving device 2A is a semiconductor integrated circuit device. Figure 2 2A is an external perspective view of the gate drive device 2A. The gate drive device 2A is an electronic component formed by sealing a semiconductor integrated circuit chip in a package made of resin. A plurality of external terminals are provided to the package of the gate drive device 2A and exposed from the package of the gate drive device 2A, and the plurality of these external terminals include Figure 1 The terminals PWM1, PWM2, and terminals EN, VB, VCP, G1H, S1H, G1L, S1L, G2H, S2H, G2L, and S2L are shown. Note that the number of external terminals of the gate drive device 2A and the appearance of the gate drive device 2A, Figure 2 The external terminals and appearance shown are merely examples.

[0050] The gate driving device 2A includes a control logic unit 20, gate driving circuits 21 to 24, and an internal power supply circuit 25. The gate driving device 2A also includes terminals PWM1, PWM2, EN, VB, VCP, G1H, S1H, G1L, S1L, G2H, S2H, G2L, and S2L.

[0051] The control logic unit 20 supplies a signal based on a first PWM signal supplied to a terminal PWM1 to gate drive circuits 21 and 22. The control logic unit 20 supplies a signal based on a second PWM signal supplied to a terminal PWM2 to gate drive circuits 23 and 24.

[0052] The internal power supply circuit 25 converts the voltage Vb into a stable internal power supply voltage Vcc, and the voltage Vb is applied to the terminal VB. In a state where the enable signal applied to the terminal EN is already at a first level (e.g., a low level), the control logic unit 20 and the internal power supply circuit 25 are in an enabled state. On the other hand, in a state where the enable signal applied to the terminal EN is already at a second level (e.g., a high level), the control logic unit 20 and the internal power supply circuit 25 are in a disabled state.

[0053] The gate drive circuit 21 includes switching devices Q1 and Q2. The switching device Q1 is a P-channel MOSFET. The switching device Q2 is an N-channel MOSFET. The control logic unit 20 complementarily turns on and off the switching devices Q1 and Q2. The switching device Q1 is a current source unit configured to allow current to flow into the gate of the switching device M1. The switching device Q2 is a current sink unit configured to draw current from the gate of the switching device M1.

[0054] The source of the switching device Q1 is connected to the terminal VCP. Outside the gate driving device 2A, the voltage Vcp is applied to the terminal VCP, and the voltage Vdd is applied to the drain of the switching device M1. The voltage Vcp is a voltage higher than the voltage Vdd. The drain of the switching device Q1 and the drain of the switching device Q2 are connected to the terminal G1H. Outside the gate driving device 2A, the gate of the switching device M1 and the first end of the resistor R1 are connected to the terminal G1H. The source of the switching device Q2 is connected to the terminal S1H. Outside the gate driving device 2A, the source of the switching device M1, the second end of the resistor R1, the drain of the switching device M2, and the first end of the motor 3 are connected to the terminal S1H. Note that the resistor R1 provided in this embodiment can be omitted.

[0055] The gate drive circuit 22 includes switching devices Q3 and Q4 and a diode D1. The switching device Q3 is a P-channel MOSFET. The switching device Q4 is an N-channel MOSFET. The control logic unit 20 complementarily turns on and off the switching devices Q3 and Q4. The switching device Q3 and the diode D1 constitute a current source unit configured to allow current to flow into the gate of the switching device M2. The switching device Q4 is a current sink unit configured to draw current from the gate of the switching device M2.

[0056] The internal power supply voltage Vcc is applied to the source of the switching device Q3. The anode of the diode D1 is connected to the drain of the switching device Q3. The cathode of the diode D1 and the drain of the switching device Q4 are connected to the terminal G1L. Outside the gate driving device 2A, the gate of the switching device M2, the first end of the resistor R2, and the first end of the switch SW1 are connected to the terminal G1L. The source of the switching device Q4 is connected to the terminal S1L. Outside the gate driving device 2A, the source of the switching device M2, the second end of the resistor R2, and the ground potential are connected to the terminal S1L. Note that the resistor R2 provided in this embodiment can be omitted.

[0057] The gate drive circuit 23 includes switching devices Q5 and Q6. The switching device Q5 is a P-channel MOSFET. The switching device Q6 is an N-channel MOSFET. The control logic unit 20 complementarily turns on and off the switching devices Q5 and Q6. The switching device Q5 is a current source unit configured to allow current to flow into the gate of the switching device M3. The switching device Q6 is a current sink unit configured to draw current from the gate of the switching device M3.

[0058] Similar to the source of the switching device Q1, the source of the switching device Q5 is connected to the terminal VCP. The drain of the switching device Q5 and the drain of the switching device Q6 are connected to the terminal G2H. Outside the gate driving device 2A, the gate of the switching device M3 and the first end of the resistor R3 are connected to the terminal G2H. The source of the switching device Q6 is connected to the terminal S2H. Outside the gate driving device 2A, the source of the switching device M3, the second end of the resistor R3, the drain of the switching device M4, and the second end of the motor 3 are connected to the terminal S2H. Note that the resistor R3 provided in this embodiment can be omitted.

[0059] The gate drive circuit 24 includes switching devices Q7 and Q8 and a diode D2. The switching device Q7 is a P-channel MOSFET. The switching device Q8 is an N-channel MOSFET. The control logic unit 20 complementarily turns on and off the switching devices Q7 and Q8. The switching device Q7 and the diode D2 constitute a current source unit that allows current to flow into the gate of the switching device M4. The switching device Q8 is a current sink unit that is configured to draw current from the gate of the switching device M4.

[0060] The internal power supply voltage Vcc is applied to the source of the switching device Q7. The anode of the diode D2 is connected to the drain of the switching device Q7. The cathode of the diode D2 and the drain of the switching device Q8 are connected to the terminal G2L. Outside the gate driving device 2A, the gate of the switching device M4, the first end of the resistor R4, and the first end of the switch SW2 are connected to the terminal G2L. The source of the switching device Q8 is connected to the terminal S2L. Outside the gate driving device 2A, the source of the switching device M4, the second end of the resistor R4, and the ground potential are connected to the terminal S2L. Note that the resistor R4 provided in this embodiment can be omitted.

[0061] The second end of the switch SW1 and the second end of the switch SW2 are connected to the second end of the resistor R5. The voltage Vb is applied to the first end of the resistor R5. Note that the voltage applied to the first end of the resistor R5 is not limited to the voltage Vb, and any other voltage that turns on the switching device M2 when the switch SW1 is already turned on and turns on the switching device M4 when the switch SW2 is already turned on may be applied.

[0062] In a state where an enable signal at a first level (e.g., a low level) has been supplied to the terminal EN, in response to control such that the switch SW1 and the switch SW2 are turned on, the switching devices M2 and M4 are turned on to apply a short brake to the motor 3. The diode D1 prevents current from flowing from the terminal G1L to the internal power supply circuit 25 via the body diode of the switching device Q3. Thus, current consumption when a short brake is applied to the motor 3 is reduced. Similarly, the diode D2 prevents current from flowing from the terminal G2L to the internal power supply circuit 25 via the body diode of the switching device Q7. Thus, current consumption when a short brake is applied to the motor 3 is reduced.

[0063] <Second Embodiment>

[0064] Figure 3 is a schematic diagram showing a schematic structure of a motor system according to a second embodiment. Figure 3 The motor system SYS2 shown includes an MCU 1 , a gate driving device 2B, a first half-bridge circuit including switching devices M1 and M2 , a second half-bridge circuit including switching devices M3 and M4 , and a motor 3 . Figure 3 The illustrated motor system SYS2 further includes diodes D1 and D2 , resistors R1 to R5 , and switches SW1 and SW2 . The motor drive circuit composed of the gate drive device 2B, the first half-bridge circuit, and the second half-bridge circuit drives the motor 3 .

[0065] The gate driving device 2B is substantially the same as the gate driving device 2A, except that it includes terminals T1 and T2 instead of diodes D1 and D2.

[0066] Figure 3The electrical structure of the motor system SYS2 shown in the figure is similar to Figure 1 The electrical structure of the motor system SYS1 shown is basically the same. Therefore, in this embodiment, the diode D1 prevents current from flowing from the terminal G1L to the internal power supply circuit 25 via the body diode of the switching device Q3. As a result, the current consumption when a short brake is applied to the motor 3 is reduced. Similarly, the diode D2 prevents current from flowing from the terminal G2L to the internal power supply circuit 25 via the body diode of the switching device Q7. As a result, the current consumption when a short brake is applied to the motor 3 is reduced.

[0067] Note that the modification of the first embodiment is also applicable to this embodiment.

[0068] <Third Embodiment>

[0069] Figure 4 is a schematic diagram showing a schematic structure of a motor system according to a third embodiment. Figure 4 The motor system SYS3 shown includes an MCU 1 , a gate driving device 2C, a first half-bridge circuit including switching devices M1 and M2 , a second half-bridge circuit including switching devices M3 and M4 , and a motor 3 . Figure 4 The motor system SYS3 shown further includes resistors R1 to R4 , a resistor R6 , and a switch SW3 . The motor drive circuit composed of the gate drive device 2C, the first half-bridge circuit, and the second half-bridge circuit drives the motor 3 .

[0070] The gate drive device 2C is substantially the same as the gate drive device 2A except for including a terminal BRKB and a brake circuit 26. The brake circuit 26 is a circuit corresponding to the resistor R5, the switch SW1, and the switch SW2 in the first embodiment.

[0071] The braking control signal is supplied to the terminal BRKB. The resistor R6 and the switch SW3 are examples of a circuit that generates the braking control signal. The voltage Vb is applied to the first end of the resistor R6. Outside the gate drive device 2C, the second end of the resistor R6 and the first end of the switch SW3 are connected to the terminal BRKB. The second end of the switch SW3 is connected to the ground potential.

[0072] In this embodiment, the short brake is applied to the motor 3 while the brake control signal is already at a low level. Therefore, the control switch SW3 is turned on when the short brake is applied to the motor 3. Note that, unlike this embodiment, the short brake may be applied to the motor 3 while the brake control signal is already at a high level.

[0073] When the brake control signal is already at a low level, the brake circuit 26 allows current to flow into the gate of each of the switching devices M2 and M4. On the other hand, when the brake control signal is already at a high level, the brake circuit 26 does not allow current to flow into the gate of each of the switching devices M2 and M4.

[0074] Also in this embodiment, as in the first and second embodiments, the diode D1 prevents current from flowing from the terminal G1L to the internal power supply circuit 25 via the body diode of the switching device Q3. Thus, current consumption is reduced when a short brake is applied to the motor 3. Similarly, the diode D2 prevents current from flowing from the terminal G2L to the internal power supply circuit 25 via the body diode of the switching device Q7. Thus, current consumption is reduced when a short brake is applied to the motor 3.

[0075] Note that the modification of the first embodiment is also applicable to this embodiment. In addition, this embodiment can also be modified similarly to the modification from the first embodiment to the second embodiment.

[0076] <Fourth Embodiment>

[0077] Figure 5 is a schematic diagram showing a schematic structure of a motor system according to a fourth embodiment. Figure 5 The motor system SYS4 shown includes an MCU 1 , a gate driving device 2D, a first half-bridge circuit including switching devices M1 and M2 , a second half-bridge circuit including switching devices M3 and M4 , and a motor 3 . Figure 5 The illustrated motor system SYS4 further includes resistors R1 to R4 , a resistor R6 , and a switch SW3 . The motor drive circuit composed of the gate drive device 2D, the first half-bridge circuit, and the second half-bridge circuit drives the motor 3 .

[0078] The gate drive device 2D is substantially the same as the gate drive device 2A, except that it includes a terminal BRKB, a brake circuit 26, and diodes D3 and D4. The brake circuit 26 is a circuit corresponding to the resistor R5, the switch SW1, and the switch SW2 in the first embodiment. The anodes of the diodes D3 and D4 are connected to the output terminal of the brake circuit 26. In the gate drive device 2D, the cathode of the diode D3 is connected to the terminal G1L, the cathode of the diode D1, and the drain of the switching device Q4. The cathode of the diode D4 is connected to the terminal G2L, the cathode of the diode D2, and the drain of the switching device Q8.

[0079] The braking control signal is supplied to the terminal BRKB. The resistor R6 and the switch SW3 are examples of a circuit that generates the braking control signal. The voltage Vb is applied to the first end of the resistor R6. Outside the gate drive device 2D, the second end of the resistor R6 and the first end of the switch SW3 are connected to the terminal BRKB. The second end of the switch SW3 is connected to the ground potential.

[0080] In this embodiment, the short brake is applied to the motor 3 while the brake control signal is already at a low level. Therefore, the control switch SW3 is turned on when the short brake is applied to the motor 3. Note that, unlike this embodiment, the short brake may be applied to the motor 3 while the brake control signal is already at a high level.

[0081] In the state where the brake control signal is already at a low level, the brake circuit 26 allows current to flow into the gate of each of the switching devices M2 and M4. On the other hand, in the state where the brake control signal is already at a high level, the brake circuit 26 does not allow current to flow into the gate of each of the switching devices M2 and M4. In addition, in this embodiment, in the state where the brake control signal is already at a high level, the power supply 262 (hereinafter referred to as Figure 6 and Figure 7 The output voltage is 0V.

[0082] Without the diodes D3 and D4, in a state where the braking control signal is already at a high level and a high-level signal is output from the gate drive circuits 22 and 24, current flows from the gate drive circuits 22 and 24 to the braking circuit 26. In this embodiment, the diodes D3 and D4 are provided. Therefore, even in a state where the braking control signal is already at a high level and a high-level signal is output from the gate drive circuits 22 and 24, current can be prevented from flowing from the gate drive circuits 22 and 24 to the braking circuit 26.

[0083] Also in this embodiment, as in the first to third embodiments, the diode D1 prevents current from flowing from the terminal G1L to the internal power supply circuit 25 via the body diode of the switching device Q3. Thus, current consumption is reduced when a short brake is applied to the motor 3. Similarly, the diode D2 prevents current from flowing from the terminal G2L to the internal power supply circuit 25 via the body diode of the switching device Q7. Thus, current consumption is reduced when a short brake is applied to the motor 3.

[0084] Figure 6 is a schematic diagram showing an example of the structure of the brake circuit 26 to be used in the embodiment of the present disclosure. Figure 6The brake circuit 26 shown includes a control circuit 261, a power supply 262, a resistor 263, a Zener diode 264 and a switch 265. The switch 265 is a P-channel MOSFET. The switch 265 is between the power supply 262 and the diodes D3 and D4 ( Figure 6 not shown).

[0085] The control circuit 261 and the power supply 262 use the voltage Vb applied to the terminal VB as a power supply voltage. Therefore, even when the internal power supply circuit 25 is in a disabled state, the control circuit 261 and the power supply 262 are operable.

[0086] In response to the brake control signal supplied to the terminal BRKB, the control circuit 261 turns on / off the switch 265. Specifically, the control circuit 261 turns on the switch 265 when the brake control signal is already at a low level, and turns off the switch 265 when the brake control signal is already at a high level.

[0087] The power supply 262 is configured to be turned on / off in response to the brake control signal supplied to the terminal BRKB. Specifically, the power supply 262 is turned on (enabled state) when the brake control signal is already at a low level, and is turned off (disabled state) when the brake control signal is already at a high level. Thus, the power consumption of the brake circuit 26 can be reduced when the short brake is not applied to the motor 3 (that is, when the brake control signal is already at a high level).

[0088] Figure 7 It is shown Figure 6 FIG. 2 is a schematic diagram showing an example of the configuration of a control circuit 261 and a power supply 262 of the brake circuit 26 . Figure 7 The control circuit 261 and the power supply 262 shown are each composed of a resistor, a MOSFET, a Zener diode, and a diode.

[0089] Note that the modification of the first embodiment is also applicable to this embodiment. In addition, this embodiment can also be modified similarly to the modification from the first embodiment to the second embodiment.

[0090] <Application Examples>

[0091] Figure 8 It is a view showing the appearance of a vehicle. Figure 8 The vehicle X1 shown comprises a motor system according to any of the above-described embodiments or variations thereof.

[0092] The motor system according to the above-described embodiment or its modifications can be applied to various vehicle-mounted systems provided to the vehicle X 1. Herein, an example in which the motor system is applied to a power window system as an example of a vehicle-mounted system is described.

[0093] Fig. 9 is a schematic diagram showing an example of the structure of a power window system to which the motor system is applied. Fig. 9 The electric window system Y1 shown is a system for actuating a window Y2 and includes the window Y2, a motor system Y3 and a regulator Y4.

[0094] The adjuster Y4 is a so-called arm-type adjuster, that is, a mechanism that moves the window Y2 up / down by the rotational drive of the motor included in the motor system Y3. Note that other adjusters such as so-called linear adjusters may also be adopted. The window Y2 includes, for example, the front and rear windows Y2 arranged on both sides of the vehicle X1.

[0095] The position of the vehicle window Y2 in the up-down direction is adjusted by the rotational drive of the motor included in the motor system Y3. Then, the motor included in the motor system Y3 enters a short braking state to fix the position of the vehicle window Y2. During most of the time when the vehicle X1 is driven, the motor included in the motor system Y3 is in the short braking state. In addition, when parking, the motor included in the motor system Y3 is also in the short braking state. In this state, the position of the vehicle window Y2 is fixed, and thus the crime deterrence effect can be enhanced.

[0096] The motor system according to the above-described embodiment or its variations can also be applied to various other vehicle-mounted systems, such as an electric sunroof system and an electric sliding door system. The vehicle-mounted system utilizes power output from a battery installed in the vehicle X1. Therefore, the motor system according to the above-described embodiment or its variations, which can reduce current consumption, is particularly useful.

[0097] The vehicle-mounted system to which the motor system according to the above-described embodiment or its variation is applicable enables the omission of a locking mechanism for restricting the movement of a component such as a vehicle window. Therefore, cost reduction and size reduction can be achieved.

[0098] A motor system according to the above-described embodiment or its variations (which is capable of reducing current consumption) is particularly useful not only in vehicle-mounted systems but also in systems in which commercial power cannot be used and in which the position of a component that can be moved by the rotational drive of a motor needs to be locked.

[0099] The motor system according to the above embodiment or its variations is applicable to systems not limited to systems that cannot use commercial power. The motor system according to the above embodiment or its variations can be applied to, for example, a damper position adjustment system and a blind opening and closing system of an air conditioner.

[0100] <Others>

[0101] The structure disclosed herein can be implemented as in the above-mentioned embodiments, or various modifications can be made within the subject matter of the present disclosure. All features of the above-mentioned embodiments are merely examples, and therefore should not be considered as limitations. It should be understood that the technical scope of the present disclosure is not limited by the above-mentioned embodiments, but by the scope of the claims, and covers the meaning of the equivalents of the elements described within the scope of the claims and all modifications within the scope of the claims.

[0102] For example, the motor which is a two-phase motor in the above-mentioned embodiment may be a three-phase motor. In addition, when the motor is a three-phase motor, there is no problem as long as the motor system includes three half-bridge circuits.

[0103] <Appendix>

[0104] Now, an appendix of the present disclosure, specifically, an appendix of specific structural examples described in the above-mentioned embodiments is provided.

[0105] The gate drive circuit (22, 24) according to the present disclosure has a structure (first structure) for driving the gate of the second switching device (M2, M4) in the motor drive circuit (2A to 2D, M1 to M4),

[0106] The motor driving circuit includes a plurality of half-bridge circuits, each of which includes:

[0107] a first switching device (M1, M3), and

[0108] The second switching device,

[0109] The second switching device is connected in series to the first switching device, and

[0110] the second switching device is arranged on a low potential side relative to the first switching device,

[0111] The motor driving circuit is configured to drive a motor (3),

[0112] The gate drive circuit comprises:

[0113] a current source unit (Q3, D1, Q7, D2) configured to allow current to flow into the gate of the second switching device; and

[0114] a current sink unit (Q4, Q8) configured to draw current from the gate of the second switching device,

[0115] The current source unit includes a first diode (D1, D2) disposed in an orientation where a cathode of the first diode points to a side where the gate of the second switching device exists.

[0116] According to the gate drive circuit having the first structure, it is possible to prevent current from flowing through the current source unit when a short brake is applied to the motor, thereby reducing current consumption when a short brake is applied to the motor.

[0117] The gate driving device (2A to 2D) according to the present disclosure has a structure (second structure) including the following:

[0118] A gate driving circuit having a first structure; and

[0119] A first switching device gate drive circuit (21, 23), wherein the first switching device gate drive circuit is configured to drive a gate of the first switching device.

[0120] The gate driving device having the second structure may have a structure (third structure) including the following:

[0121] A brake circuit (26) is configured to allow current to flow into the gate of the second switching device in response to a brake control signal.

[0122] The gate driving device having the third structure may have a structure (fourth structure) including the following:

[0123] The second diode (D3, D4),

[0124] wherein the second diode is interposed between the brake circuit and the gate of the second switching device in an orientation in which the cathode of the second diode points to the side where the gate of the second switching device is present, and

[0125] The brake circuit includes a power supply (262) configured to be turned on / off in response to the brake control signal.

[0126] The gate driving device having the fourth structure may have a structure (fifth structure),

[0127] wherein the braking circuit comprises a switch (265), and

[0128] wherein the switch is interposed between the power supply and the second diode, and

[0129] The switch is configured to be subjected to on / off control in response to the brake control signal.

[0130] The gate driving device having any one of the second to fifth structures may have a structure (sixth structure) in which the gate driving device is a semiconductor integrated circuit device.

[0131] The motor system (SYS1 to SYS4) according to the present disclosure has a structure (seventh structure) including the following:

[0132] A gate driving device having any one of the second to sixth structures;

[0133] the motor drive circuit; and

[0134] The motor.

[0135] A vehicle (X1) according to the present disclosure has a structure (eighth structure) including the motor system having the seventh structure.

[0136] In the current consumption reduction method according to the present disclosure,

[0137] The motor drive circuit (2A to 2D, M1 to M4) includes a plurality of half-bridge circuits, each of which includes:

[0138] a first switching device (M1, M3), and

[0139] The second switch device (M2, M4),

[0140] The second switching device is connected in series to the first switching device, and

[0141] the second switching device is arranged on a low potential side relative to the first switching device,

[0142] The motor drive circuit is configured to drive a motor (3), and

[0143] The current consumption reduction method includes providing a diode (D1, D2) in a current source unit (Q3, D1, Q7, D2), the current source unit being configured to allow current to flow into the gate of the second switching device, and the diode being arranged in an orientation in which the cathode of the diode points to a side where the gate of the second switching device exists, thereby reducing the current consumption when a short brake is applied to the motor.

[0144] In addition, according to the current consumption reduction method of the present disclosure, it is possible to prevent current from flowing through the current source unit when a short brake is applied to the motor, thereby reducing the current consumption when a short brake is applied to the motor.

Claims

1. A gate drive circuit configured to drive a gate of a second switching device in a motor drive circuit, The motor driving circuit includes a plurality of half-bridge circuits, each of which includes: a first switching device, and the second switch device, The second switching device is connected in series to the first switching device, and the second switching device is arranged on a low potential side relative to the first switching device, The motor drive circuit is configured to drive the motor, The gate drive circuit comprises: a current source unit configured to allow current to flow into the gate of the second switching device; and a current sink unit configured to draw current from the gate of the second switching device, The current source unit includes a first diode disposed in an orientation where a cathode of the first diode points to a side where the gate of the second switching device exists.

2. A gate driving device, comprising: The gate drive circuit according to claim 1; as well as A first switching device gate drive circuit is configured to drive a gate of the first switching device.

3. The gate driving device according to claim 2, further comprising: A brake circuit is configured to allow current to flow into the gate of the second switching device in response to a brake control signal.

4. The gate driving device according to claim 3, further comprising: The second diode, wherein the second diode is interposed between the brake circuit and the gate of the second switching device in an orientation in which the cathode of the second diode points to the side where the gate of the second switching device is present, and The brake circuit includes a power supply configured to be turned on / off in response to the brake control signal.

5. The gate driving device according to claim 4, wherein the brake circuit comprises a switch, and wherein the switch is interposed between the power supply and the second diode, and The switch is configured to be subjected to on / off control in response to the brake control signal.

6. The gate driving device according to any one of claims 2 to 5, The gate driving device is a semiconductor integrated circuit device.

7. A motor system comprising: The gate driving device according to any one of claims 2 to 6; the motor driving circuit; as well as The motor.

8. A vehicle comprising: The motor system according to claim 7.

9. A method for reducing current consumption, wherein a motor driving circuit comprises a plurality of half-bridge circuits, each half-bridge circuit comprising: a first switching device, and The second switching device, The second switching device is connected in series to the first switching device, and The second switching device is provided on a low potential side relative to the first switching device, and wherein the motor drive circuit is configured to drive the motor, The current consumption reduction method includes providing a diode in a current source unit, the current source unit being configured to allow current to flow into the gate of the second switching device, and the diode being arranged in an orientation with the cathode of the diode pointing to a side where the gate of the second switching device is present, thereby reducing the current consumption when a short brake is applied to the motor.

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