JP5914299B2 - Motor control device - Google Patents

Description

  The present invention relates to a motor control device that controls power supply from a power source to a motor, and more particularly to a motor control device that controls power supply to a motor by switching operation of a field effect transistor.

Among motor control devices that control power supply from a power source to a motor, there is a device that controls power supply to a motor by a switching operation of a field effect transistor (hereinafter referred to as FET) such as a MOSFET (for example, , See Patent Document 1). For example, Patent Literature 1 discloses a motor control device (indicated as a motor control circuit in Patent Literature 1) incorporated in a vehicle power window device as an example of the motor control device described above.
The motor control device disclosed in Patent Document 1 includes an FET disposed between the motor and the ground for switching the power supply state from the power source to the motor, a controller that outputs a control signal for turning on the FET, It has. In the motor control device disclosed in Patent Document 1, it is possible to perform PMW control on the rotation speed of the motor by the controller outputting a control signal at a predetermined duty ratio.

  By the way, it is necessary to stop the rotation of the motor while the ignition switch of the vehicle is off. For this reason, while the ignition switch is off, control to ground both terminals of the motor to the ground, that is, motor brake control. May be executed. Here, in the motor control device including the FET and the controller, normally, when the ignition switch is turned off, the power supply to the controller is cut off, so that the output of the control signal from the controller is interrupted. As a result, the FET is turned off. However, if the FET remains in the off state, both terminals of the motor cannot be grounded. As a measure for correcting such a problem, it is conceivable to maintain power supply to the controller for a predetermined time after the ignition switch is turned off by incorporating a delay circuit in the motor control device (for example, Patent Document 2). reference).

JP 2005-133449 A JP-A-6-108734

However, even if the measures described in Patent Document 2 are taken, the gate energization of the FET is cut off after the lapse of the delay time, so that the ignition switch is turned off in order to maintain the FET energization of the FET. After that, the controller will continue to start. As a result, power is consumed more than necessary, and so-called battery exhaustion is eventually caused.
On the other hand, for the purpose of reducing power consumption while the ignition switch is off, it is conceivable to start the controller intermittently (wake up) instead of always starting it. However, when the controller is activated intermittently, the power consumption fluctuates, and particularly the power consumption immediately after the controller is activated becomes overwhelming. As a result, power consumption can be suppressed as compared with the case where the controller is always started, but power consumption still increases.

  Accordingly, the present invention has been made in view of the above-described problems, and an object of the present invention is to control a field effect transistor as a motor control device that controls power supply to a motor by switching operation of the field effect transistor. An object of the present invention is to provide a motor control device capable of maintaining the gate energization of a field effect transistor while suppressing power consumption while a control circuit to be operated is not activated.

  According to the motor control device of the present invention, one of a power supply path laid to supply power from a power source to the motor, a drain terminal, and a source terminal is connected to the motor. A field effect transistor disposed in the power supply path with the other terminal connected to the ground, a control circuit for applying a control voltage to the gate terminal of the field effect transistor when in the activated state, and one end Is connected to the control circuit and the other end is connected to the gate terminal, and the first path is branched from a position of the power supply path located between the power source and the motor. A second path connected to the second terminal and the other terminal and the gate terminal, and is turned on when the control circuit is in the activated state, and the control circuit applies the control voltage to the gate terminal. A switch that is turned off when in a non-starting state not added, a first resistor arranged between the other terminal and the gate terminal so as to be arranged in series with the switch, and in the second path This is solved by having a second resistor arranged.

  In the case of the motor control device described above, the control circuit for controlling the field effect transistor is not activated, and is disposed between the terminal of the field effect transistor that is grounded and the gate terminal. The switch turns off. As a result, the potential of the terminal grounded to the ground becomes the ground potential, and the potential of the gate terminal becomes the power supply potential (more strictly, the anode potential of the power supply). As described above, when the control circuit is in the non-starting state, the potentials are different between the two terminals, so that a voltage corresponding to the potential difference between the terminals is applied to the gate terminal of the field effect transistor. This makes it possible to maintain the gate energization of the field effect transistor even during a period when the control circuit is not activated. Furthermore, since the gate energization of the field effect transistor is maintained without activating the control circuit, it is possible to suppress power consumption compared to the case where the control circuit is activated constantly or intermittently.

In the motor control device, a push-pull type amplifier that amplifies the control voltage is provided in the middle of the first path, and is connected in series with each other in the push-pull type amplifier. Among the two bipolar transistors, another switch is connected to the bipolar transistor side having a ground terminal grounded to the ground, and the other switch is turned on when the control circuit is in the activated state. It is preferable that the control circuit is turned off when the control circuit is in the non-activated state.
With the above configuration, during the period when the control circuit is not activated, the transistor having the ground terminal (that is, the low-side transistor) is turned on among the two bipolar transistors provided in the push-pull amplifier. For this reason, if the current path is energized from the anode of the power source to the ground via the first path and the low-side transistor during the period when the control circuit is not activated, the current is passed through the path. It continues to flow and power consumption increases. On the other hand, if a switch is connected to the low-side transistor, the switch can be turned off while the control circuit is not activated to cut off the current and suppress power consumption.

In the motor control device described above, the resistance value of the second resistor is more preferably 100 kΩ or more.
In the above configuration, when the field effect transistor is switched from the on-state to the off-state, the low-side transistor of the two bipolar transistors provided in the push-pull amplifier is turned on. For this reason, a current flows from the anode of the power source to the ground via the first path and the low-side transistor. At this time, if a resistor of 100 kΩ or more is arranged on the second path, the magnitude of the current flowing through the above path becomes small, so that power consumption can be suppressed.

In the motor control device described above, both the switch and the other switch are turned on while receiving a control signal output from the control circuit, and the control circuit is switched from the activated state to the non-switched state. More preferably, the output of the control signal is interrupted at the time of switching to the activated state.
With the configuration described above, each of the switches and the other switches is switched on and off as the state of the control circuit is switched from the activated state to the non-activated state. That is, when the control circuit is switched from the activated state to the non-activated state, each switch is automatically switched from on to off. As a result, it is possible to appropriately switch on / off of each switch according to the state of the control circuit.

In the motor control device, the motor is a vehicle motor for opening and closing an opening / closing body provided in the vehicle, and an ignition switch provided in the vehicle is turned on in the control circuit. Sometimes it is in the activated state, it is in the inactivated state when the ignition switch is off, and during the period when the ignition switch is off, both terminals of the vehicle motor are connected via the field effect transistor If it is grounded to the ground, the effect of the present invention becomes more significant.
That is, in a configuration in which the opening / closing body provided in the vehicle is driven to open and close by the motor, it is necessary to stop the rotation of the motor to keep the opening / closing body stationary while the ignition switch is off. To stop the rotation of the motor, both terminals of the motor must be grounded while the ignition switch is off. To ground both terminals of the motor, the field effect transistor must be kept on. There is a need to. For this reason, the effect of the present invention is more meaningful to maintain the gate conduction of the field effect transistor while suppressing the power consumption while the ignition switch is off, that is, while the control circuit is not activated. .

According to the motor control device of the present invention, while the control circuit is not activated, among the terminals of the field effect transistor, the potential of the terminal grounded to the ground becomes the ground potential, and the potential of the gate terminal becomes the power supply potential. Become. As a result, since a voltage corresponding to the potential difference between the two terminals is continuously applied to the gate terminal of the field effect transistor, the gate conduction of the field effect transistor can be maintained. Furthermore, since the gate conduction of the field effect transistor is maintained without starting the control circuit, it is possible to suppress power consumption compared to the case where the control circuit is started.
Further, in the motor control device of the present invention, during the period when the control circuit is not activated, the current flowing from the power source to the ground via the push-pull amplifier is cut off, thereby further reducing the power consumption. It becomes possible to suppress.
Furthermore, with the motor control device of the present invention, when the field effect transistor is turned off, the power consumption is further suppressed by cutting off the current flowing from the power source to the ground via the push-pull amplifier. Is possible.
Furthermore, with the motor control device of the present invention, it is possible to automatically switch on / off of the switches in the circuit according to the state of the control circuit.
Furthermore, if the motor control device of the present invention is used to control a vehicle motor for opening and closing an opening / closing body provided in the vehicle, the motor rotation is stopped even during a period in which the ignition switch is off. Therefore, the opening / closing body can be securely held stationary.

It is a schematic diagram which shows the machine structure of a power window apparatus. It is the block diagram which showed the structure of the power window apparatus containing the motor control apparatus of this invention. It is a circuit diagram which shows the 1st structural example of the motor control apparatus of this invention. It is a circuit diagram which shows the 2nd structural example of the motor control apparatus of this invention. It is a circuit diagram which shows the structure of the conventional relay drive type motor control apparatus. It is a circuit diagram which shows the structure of the conventional H bridge type motor control apparatus. FIG. 5 is an equivalent circuit for an amplifier arranged in a high-voltage side path in FIG. 4. FIG. 5 is an equivalent circuit for an amplifier arranged on a low-pressure side path in FIG. 4.

Hereinafter, as an example of a motor control device of the present invention, a power window electronic control unit (hereinafter, referred to as a “control unit”) ECU incorporated in a power window device PW of a vehicle will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing a mechanical configuration of a power window device. FIG. 2 is a block diagram showing a configuration of a power window device including the motor control device of the present invention. FIG. 3 is a circuit diagram showing a first configuration example of the motor control device of the present invention. FIG. 4 is a circuit diagram showing a second configuration example of the motor control device of the present invention. FIG. 5 is a circuit diagram showing a configuration of a conventional relay drive type motor control device. FIG. 6 is a circuit diagram showing a configuration of a conventional H-bridge type motor control device. FIG. 7A is an equivalent circuit for an amplifier arranged in a high-voltage side path to be described later in FIG. FIG. 7B is an equivalent circuit for an amplifier arranged in a low-pressure side path to be described later in FIG.

  The following description is based on the case where the battery B is sequentially connected to the motor drive circuit MC unless otherwise specified (the battery B and the motor drive circuit MC will be described later). In the direction in which the current flows along, the side closer to the anode of the battery B is called the upstream side, and the side closer to the cathode is called the downstream side.

  The present control unit ECU controls a vehicle motor (hereinafter simply referred to as a motor) M for driving to open and close a window glass WD as an opening / closing body provided in the vehicle. The power window device PW has a known configuration except for the control unit ECU. An example of the configuration of the power window device PW will be outlined with reference to FIG. 1. A window glass WD is disposed in the vehicle door DR so as to be movable up and down, and an X arm type lifting mechanism XM disposed in the vehicle door DR is also provided. The window glass WD is moved up and down using the power of the motor M transmitted through the gear GR.

  The motor M rotates by being supplied with electric power from a battery B as a power source mounted on the vehicle. Then, the control unit ECU supplies power from the battery B to the motor M. More specifically, as shown in FIG. 2, the present control unit ECU has a motor drive circuit MC as an electric power supply path, and supplies electric power from the battery B to the motor through the circuit MC. That is, the motor drive circuit MC is laid to supply electric power from the battery B to the motor M.

  Furthermore, as shown in FIG. 2, the control unit ECU is provided with a control circuit 18. The control circuit 18 is composed of a microcomputer, and starts by receiving power from the battery B via the motor drive circuit MC. More specifically, during a period in which an ignition switch IG provided in the vehicle is on, the control circuit 18 receives power from the battery B and maintains the activated state. Then, the control circuit 18 in the activated state controls the rotation of the motor M by controlling the power supply to the motor M.

That is, when the closing switch UP is operated while the ignition switch IG is on, the control circuit 18 turns on the motor drive circuit MC so that the current passes through the motor M in the forward direction. Control each part. Thereby, the electric power from the battery B is supplied to the motor M, the motor M rotates forward, and the window glass WD rises (closes).
Similarly, when the open switch DN is operated while the ignition switch IG is on, the control circuit 18 energizes the motor drive circuit MC and the current in the motor M is in the reverse direction (what is the forward direction? Each part in the circuit is controlled to pass in the opposite direction. Thereby, the electric power from the battery B is supplied to the motor M, the motor M is reversed, and the window glass WD descends (opens movement).

  The control circuit 18 can also control the power supply to the motor M to perform PWM control on the rotation speed of the motor M. Specifically, as shown in FIG. 2, the motor M includes a rotation detection device RD, and the rotation detection device RD directs a pulse signal corresponding to the rotation speed of the motor M to the control circuit 18. Output. On the other hand, in the motor drive circuit MC, as shown in FIGS. 3 and 4, MOS transistors (hereinafter referred to as MOSFETs) as field effect transistors are arranged in series with the motor M.

When the control circuit 18 receives a pulse signal from the rotation detection device RD while in the activated state, the control circuit 18 applies a control voltage to the gate terminal of the MOSFET with a duty ratio corresponding to the signal. Thereby, the on / off of the MOSFET is switched at a frequency corresponding to the duty ratio, and the voltage applied to the motor M is adjusted to a magnitude corresponding to the duty ratio. As a result, the rotational speed of the motor M is controlled to a speed corresponding to the duty ratio.
As described above, the control unit ECU adjusts the elevation speed of the window glass WD by PWM control of the rotation speed of the motor M. As a result, when the window glass WD is fully opened or closed, it is possible to reduce the ascending / descending speed of the window glass WD so that the window glass WD collides against the window frame or the like to generate an impact sound. Become.

Note that, when the ignition switch IG is turned off, the power supply from the battery B to the control circuit 18 is cut off, and as a result, the control circuit 18 enters a non-activated state. The control circuit 18 does not apply a control voltage to the gate terminal of the MOSFET when it is in a non-starting state.
On the other hand, in the present control unit ECU, when the ignition switch IG is turned off, motor brake control for stopping the motor rotation is executed. By executing such control, it is possible to reliably hold the window glass WD stationary while the ignition switch IG is off. Here, the motor brake control is a control for stopping the rotation of the motor M by grounding both the input terminals of the motor M corresponding to the terminals of the vehicle motor to the ground and short-circuiting the two input terminals. That is.

<< First configuration example of the control unit >>
A first configuration example of the control unit ECU will be described with reference to FIG.
The present control unit ECU (hereinafter referred to as the first unit U1) according to the first configuration example is a so-called relay drive type motor control device, as shown in FIG. 3, in addition to the control circuit 18 and the motor drive circuit MC described above. Two relays 108 and 109 are provided.

  First, the motor drive circuit MC will be described. When the battery B is sequentially connected to the motor drive circuit MC, the terminal on the (+) side of the motor drive circuit MC is connected to the anode of the battery B through the fuse H. The terminal on the (−) side is connected to the cathode of the battery B. Since the cathode of the battery B is grounded as shown in FIG. 3, the terminal on the (−) side of the motor drive circuit MC is grounded.

The motor drive circuit MC includes a high-voltage side line MCh connected to the anode of the battery B and a low-voltage side line MCl connected to the ground as main components. The high-voltage side line MCh extends from the (+) side terminal connected to the anode of the battery B, and its downstream end branches to be the first contact of each of the relays 108 and 109 (the symbol a in FIG. Attached contact). In the motor drive circuit MC, the low-pressure side line MC1 is branched at the upstream end thereof and connected to the second contacts of the relays 108 and 109 (contacts marked with symbol b in FIG. 3). The battery B extends toward the (−) terminal connected to the cathode of the battery B.
As shown in FIG. 3, a branch path extends from a location slightly downstream from the upstream end of the high-pressure side line MCh toward a location slightly upstream from the downstream end of the low-pressure side line MCl. A noise removing capacitor 1 is disposed in the middle of the branch path. In addition, the noise elimination inductor 2 is disposed at a location slightly downstream from the extension start point of the branch path in the high voltage side line MCh.

  Next, the control circuit 18 will be described. The control circuit 18 is composed of a microcomputer as described above, and receives power from the battery B through a branch path (hereinafter referred to as a microcomputer power supply circuit) branched from the motor drive circuit MC. . More specifically, the microcomputer power supply circuit is branched slightly from the (+) side terminal of the motor drive circuit MC and is connected to the control circuit 18. Further, a constant voltage power supply circuit 17 is disposed in the middle of the power supply circuit for the microcomputer. The constant voltage power supply circuit 17 steps down the anode voltage (for example, 12V) of the battery B to 5V, and the voltage after the step down is operated. The voltage is supplied to the control circuit 18.

  In the microcomputer power supply circuit, a reverse connection prevention diode 9 is arranged on the upstream side of the constant voltage power supply circuit 17, and the battery drive circuit MC is connected to the motor drive circuit MC when the battery B is reversely connected to the motor drive circuit MC. The reverse current is prevented from flowing. Further, a power supply instantaneous interruption preventing capacitor 10 is connected between the constant voltage power supply circuit 17 and the reverse connection prevention diode 9. The power supply instantaneous interruption prevention capacitor 10 normally stores electric power from the battery B, and discharges the electric power stored toward the control circuit 18 when power supply from the battery B to the control circuit 18 is instantaneously interrupted. It is.

  The control circuit 18 has four output terminals as shown in FIG. Of the output terminals of the control circuit 18, two output terminals are connected to the base terminals of the relay driving transistors 106 and 107. The relay driving transistors 106 and 107 are provided for each of the relays 108 and 109, and are turned on when the output voltage from the control circuit 18 is applied to the base terminal. In the first unit U1, when one of the two relay driving transistors 106 and 107 is turned on, the other is turned off.

  In the relays 108 and 109 corresponding to the relay driving transistors 106 and 107 in the ON state, an exciting current flows through the built-in exciting coil Rc, and the first contact a of the relays 108 and 109 is It is supposed to close. On the contrary, in the relays 108 and 109 corresponding to the relay driving transistors 106 and 107 in the off state, the exciting current does not flow through the exciting coil Rc, and the second contact b of the relays 108 and 109 is closed. ing. As a result, current flows in the motor drive circuit MC from the relays 108 and 109 with the first contact a closed to the relays 108 and 109 with the second contact b closed. As a result, electric power is supplied to the motor M so that the motor M rotates.

  As shown in FIG. 3, between the output terminal of the control circuit 18 and the base terminal of each of the relay driving transistors 106 and 107, base resistors 102 and 103 that suppress fluctuations in the voltage applied to the base terminal. Is arranged. Discharge resistors 104 and 105 are disposed between the base terminals and emitter terminals of the relay driving transistors 106 and 107, respectively. The discharge resistors 104 and 105 are for discharging the electric charge accumulated in the parasitic capacitance between the base terminal and the emitter terminal when the relay driving transistors 106 and 107 are turned off to determine the base potential as the ground potential.

The third output terminal of the control circuit 18 is provided to apply a control voltage to the gate terminal of a motor control transistor 113 described later. The fourth output terminal of the control circuit 18 is provided to output an ENABLE signal as a control signal toward a transistor side switch 303 and an amplifier side switch 304 described later.
The control circuit 18 outputs various signals through the above-described output terminal while receiving power from the battery B and starting up, and waits in a non-starting state without receiving power from the battery B. During this time, the output of various signals is interrupted. That is, the control circuit 18 interrupts the application of the control voltage and the output of the ENABLE signal when switching from the activated state to the non-activated state.

More specifically, the control circuit 18 is connected to the ignition switch IG via the reverse connection prevention diode 3 and the current limiting resistor 11. When the ignition switch IG is turned on, the control circuit 18 is activated by receiving power from the battery B through the above-described microcomputer power supply circuit. On the other hand, when the ignition switch IG is turned off, the power supply from the battery B to the control circuit 18 is interrupted. As a result, the control circuit 18 enters a non-activated state.
Note that, in the circuit laid between the control circuit 18 and the ignition switch IG, a branch path extends toward the ground from a position located in the middle of the reverse connection prevention diode 3 and the current limiting resistor 11. A pull-down resistor 6 is disposed in the middle of the branch path, and the pull-down resistor 6 limits the amount of current that passes through the control circuit 18 via the ignition switch IG.

  The control circuit 18 is connected to the closed switch UP via the reverse connection prevention diode 4 and the current limiting resistor 12, and is connected to the open switch DN via the reverse connection prevention diode 5 and the current limiting resistor 13. . When either the closed switch UP or the open switch DN is turned on while the control circuit 18 is in the activated state, the control circuit 18 applies a control voltage to the gate terminals of the relay driving transistors 106 and 107 corresponding to the turned on switch. Is applied.

  On the other hand, when the ignition switch IG is turned off and the control circuit 18 is switched from the activated state to the non-activated state, the gate energization of the relay driving transistors 106 and 107 is interrupted. For this reason, in the first unit U1, while the control circuit 18 is in the non-activated state, the relay driving transistors 106 and 107 are turned off, so that the second contact b is closed for both the relays 108 and 109.

  In each of the circuit laid between the control circuit 18 and the closed switch UP and the circuit laid between the control circuit 18 and the open switch DN, the current limiting resistors 12 and 13 and the reverse connection prevention diode 4 are provided. , 5, a branch path extends toward the anode of the battery B. Pull-up resistors 7 and 8 are arranged in the middle of the branch path, and the pull-up resistors 7 and 8 limit the magnitude of current passing through the control circuit 18 and the closed switch UP or the open switch DN. Is done.

  Further, in the circuit laid between the control circuit 18 and each operation switch, a branch path extends from a position closer to the control circuit 18 than the current limiting resistors 11, 12, 13 to the ground, and the branch. Pull-down resistors 14, 15, and 16 are arranged in the middle of the road. The pull-down resistors 14, 15 and 16 determine the potential at each point in the circuit connected to the switch in the off state as the ground potential.

  Incidentally, in the first unit U1, which is an example of the present control unit ECU, as described above, the control circuit 18 performs PWM control on the rotational speed of the motor M. In order to realize such control, the motor control transistor 113 is arranged in series with the motor M in the low-voltage side line MCl. The motor control transistor 113 is composed of the MOSFET described above, and is turned on when the control voltage output from the control circuit 18 is applied to the gate terminal.

  The motor control transistor 113 will be described in detail. The transistor 113 is composed of an N-type channel power MOSFET. Of the terminals of the motor control transistor 113, the drain terminal is connected to the second contact b of the relays 108 and 109, and the source terminal is connected to the (−) side terminal of the motor drive circuit MC. In other words, the motor control transistor 113 is disposed in the low-voltage side line MCl with the drain terminal connected to the motor M and the source terminal connected to the ground (grounded).

  The gate terminal of the motor control transistor 113 is connected to the output terminal of the control circuit 18. More specifically, as shown in FIG. 3, the first unit U1 includes a first path BC1 that connects the control circuit 18 and the motor control transistor 113. The first path BC1 is laid with one end connected to the output terminal of the control circuit 18 and the other end connected to the gate terminal of the motor control transistor 113.

  When the control voltage output from the control circuit 18 through the first path BC1 is applied to the gate terminal of the motor control transistor 113, the motor control transistor 113 is turned on. In the first unit U1, as described above, the rotational speed of the motor M can be PWM-controlled. That is, when the control circuit 18 applies a control voltage to the gate terminal of the motor control transistor 113 at a predetermined duty ratio, the motor control transistor 113 is turned on and off at a frequency corresponding to the duty ratio. Become.

  Here, the control circuit 18 applies the control voltage to the gate terminal of the motor control transistor 113 while the control circuit 18 is activated, that is, while the ignition switch IG is on. On the other hand, the gate energization of the motor control transistor 113 is interrupted when the control circuit 18 switches from the activated state to the non-activated state, that is, when the ignition switch IG is turned off.

  The elements around the motor control transistor 113 will be described. As shown in FIG. 3, the transistor side switch 303 and the discharge resistor 111 are arranged between the gate terminal and the source terminal of the motor control transistor 113.

  The transistor-side switch 303 corresponds to a switch, and is configured by an analog switch that can be turned on and off, for example. The transistor side switch 303 is turned on only during a period in which the ENABLE signal output from the control circuit 18 is received. That is, the transistor-side switch 303 is turned on when the control circuit 18 is in the activated state, and is turned off when the control circuit 18 is in the non-activated state where the ENABLE signal is not output. Here, the control circuit 18 in the non-starting state does not apply the control voltage to the gate terminal of the motor control transistor 113 as described above. Therefore, the transistor side switch 303 is turned off when the control circuit 18 does not apply a control voltage to the gate terminal of the motor control transistor 113.

  The discharge resistor 111 corresponds to a first resistor, and is used to discharge the charge accumulated in the parasitic capacitance between the gate terminal and the source terminal when the motor control transistor 113 is turned off to determine the gate potential as the ground potential. is there. The discharge resistor 111 is arranged between the gate terminal and the source terminal of the motor control transistor 113 in a state of being arranged in series with the transistor side switch 303, more specifically, at a position closer to the source terminal than the transistor side switch 303. Has been placed.

Examples of other elements around the motor control transistor 113 include the gate resistor 110 and the amplifier 301 arranged in the middle of the first path BC1 described above.
The gate resistor 110 suppresses fluctuations in the voltage applied to the gate terminal of the motor control transistor 113, and is farther from the transistor-side switch 303 and the discharge resistor 111 as viewed from the gate terminal of the motor control transistor 113. It is arranged at the position.

  The amplifier 301 amplifies the control voltage from the control circuit 18, and is specifically a push-pull type amplifier. The amplifier 301 will be described in detail. As shown in FIG. 3, two bipolar transistors connected in series (more specifically, in the form of an emitter follower) in the amplifier 301 constitute the amplifier 301. One of the two bipolar transistors (hereinafter referred to as a high-side transistor) 301a is an N-type channel transistor, and its collector terminal is a power supply terminal connected to the anode of the battery B. The other bipolar transistor (hereinafter, low-side transistor) 301b is a P-type channel transistor, and has a collector terminal connected to the ground.

In the first unit U1, an amplifier-side switch 304 is disposed between the two bipolar transistors in the amplifier 301. The amplifier-side switch 304 corresponds to another switch and is connected to the low-side transistor 301b in particular. In other words, the amplifier-side switch 304 is disposed closer to the low-side transistor 301b.
The amplifier side switch 304 is turned on only during a period in which the ENABLE signal output from the control circuit 18 is received. That is, the amplifier side switch 304 is turned on when the control circuit 18 is in the activated state. On the other hand, the amplifier-side switch 304 is turned off when the control circuit 18 is in a non-starting state where the ENABLE signal is not output, that is, when the control circuit 18 does not apply a control voltage to the gate terminal of the motor control transistor 113.

  As shown in FIG. 3, the second path BC2 branched from the high-voltage side line MCh of the motor drive circuit MC is connected to a position located between the gate resistor 110 and the amplifier 301 in the first path BC1. ing. The second path BC2 branches off from a midway position on the high-voltage side line MCh, that is, a position located between the anode of the battery B and the input terminal of the motor M.

  A second road-side pull-up resistor 302 is disposed in the middle of the second road BC2. The second road-side pull-up resistor 302 corresponds to a second resistor, and is used to determine the potential at the gate terminal of the motor control transistor 113 as the potential of the battery B, more specifically, the anode potential of the battery B. It is. The second road-side pull-up resistor 302 is a high-resistance resistor, and the resistance value is 100 kΩ or more.

  In addition to the devices described above, other elements are arranged in the motor drive circuit MC. For example, as shown in FIG. 3, a branch point toward the first contact a of each relay 108 and 109 in the high-voltage side line MCh and a second contact b of each relay 108 and 109 in the low-pressure side line MCl. A free-wheeling diode 112 is arranged between the branched portion. The freewheeling diode 112 is an element for preventing the motor control transistor 113 from being damaged by the back electromotive force of the motor M generated when the motor control transistor 113 is switched from on to off.

  Further, as shown in FIG. 3, the PWM ripple noise removing capacitors 19 are arranged in parallel with the motor M in the motor drive circuit MC. The PWM ripple noise removing capacitor 19 is to remove ripple noise generated due to the on / off control of the motor control transistor 113, and one terminal of the capacitor 19 is connected to the source terminal of the motor control transistor 113. The other terminal is connected to the high voltage side line MCh.

  In the first unit U1 configured as described above, even when the ignition switch IG is off, that is, during the period in which the control circuit 18 is in the non-activated state, the above-described motor brake control is executed and the window glass It is possible to reliably hold the WD stationary. Hereinafter, the effectiveness of the first unit U1 will be described in comparison with the conventional relay drive motor control unit RU1.

  The conventional relay drive type motor control device RU1 has the configuration shown in FIG. 5, and has many points in common with the first unit U1 in terms of circuit configuration. Note that, in the configuration of the conventional relay drive type motor control device RU1 illustrated in FIG. 5, the devices denoted by the same reference numerals as those in FIG. 3 are the same as those provided in the first unit U1, and thus described. Is omitted.

On the other hand, the first unit U1 employs a configuration in which the gate conduction of the motor control transistor 113 is sustainable during the period when the ignition switch IG is off, so that the conventional relay drive type motor control device RU1 is employed. Is different.
More specifically, in the conventional relay drive type motor control device RU1, it is difficult to maintain the gate energization of the motor control transistor 113 during the period when the ignition switch IG is off due to its circuit configuration. . Therefore, in order to keep the window glass WD stationary when the ignition switch IG is turned off in the conventional relay drive motor control unit RU1, it is necessary to separately provide a device for stopping the rotation of the motor M. However, in such a case, the apparatus may be increased in size and cost.

  As another method of holding the window glass WD stationary when the ignition switch IG is turned off in the conventional relay drive type motor control device RU1, it is considered that the power supply circuit from the battery B to the control circuit 18 is always energized. It is done. That is, if the control circuit 18 is maintained in the activated state even after the ignition switch IG is turned off, the motor brake control can be executed even after the ignition switch IG is turned off. However, if the power supply circuit is always energized, the power consumption will increase accordingly and the battery will run out.

  In addition, if the control circuit 18 is activated intermittently, the power consumption can be reduced to some extent. However, since the power consumption temporarily increases at the time of activation (during wakeup), the power consumption is intermittently increased. Even if the control circuit 18 is activated, the power consumption (strictly speaking, the average power consumption when the ignition switch IG is off) still increases. Further, when the control circuit 18 is started intermittently, the magnitude of the current directed to the control circuit 18 varies.

  On the other hand, the first unit U1 is connected to the transistor side switch 303 and the amplifier side switch 304, the first path BC1 connecting the control circuit 18 and the gate terminal of the motor control transistor 113, and the first unit U1. A second path BC2 and a second path side pull-up resistor 302 disposed in the second path BC2 are provided. Thereby, when the ignition switch IG is turned off, the motor brake control is executed, the window glass WD is held stationary, and the power consumption required for executing the motor brake control can be suppressed.

  More specifically, while the ignition switch IG is on, the control circuit 18 is in an activated state and outputs an ENABLE signal to each of the transistor side switch 303 and the amplifier side switch 304. That is, while the control circuit 18 is in the activated state, the transistor side switch 303 and the amplifier side switch 304 are each kept on. Accordingly, when the control circuit 18 outputs a control voltage toward the gate terminal of the motor control transistor 113, each of the two bipolar transistors constituting the amplifier 301 is turned on, and the amplified control voltage output from the amplifier 301 is turned on. Is applied to the gate terminal of the motor control transistor 113. As a result, the motor control transistor 113 is turned on.

  Further, since each of the transistor side switch 303 and the amplifier side switch 304 is maintained in the on state while the ignition switch IG is on, when the control circuit 18 outputs the control voltage at a predetermined duty ratio, the duty ratio The motor control transistor 113 is turned on and off at a frequency according to the above. Here, when the motor control transistor 113 is turned off, the transistor-side switch 303 is turned on, so that the charge accumulated in the parasitic capacitance between the gate terminal and the source terminal of the motor control transistor 113 is discharged to the gate potential. Can be determined at the ground potential.

On the other hand, when the ignition switch IG is turned off, the control circuit 18 enters a non-activated state, and interrupts application of the control voltage to the gate terminal of the motor control transistor 113.
Further, when the control circuit 18 is in a non-activated state, the output of the ENABLE signal to each of the transistor side switch 303 and the amplifier side switch 304 is interrupted. That is, when the control circuit 18 is switched from the activated state to the non-activated state, the transistor side switch 303 is turned off. As a result, the path between the gate terminal and the source terminal of the motor control transistor 113 is blocked, and the discharge of electric charges (gate discharge) through the path is interrupted.

  Further, the path between the gate terminal and the source terminal of the motor control transistor 113 is cut off, thereby generating a potential difference between the two terminals. More specifically, since the gate terminal is connected to the anode of the battery B via the second road side pull-up resistor 302, the potential is fixed to the anode potential of the battery B. On the other hand, since the source terminal is grounded to the ground, the potential is fixed to the ground potential. As a result, a potential difference is generated between the gate terminal and the source terminal. In other words, a voltage (power supply voltage) corresponding to the potential difference is applied to the gate terminal of the motor control transistor 113. As a result, the motor control transistor 113 can be maintained in the ON state even during the period when the ignition switch IG is turned off and the application of the control voltage by the control circuit 18 is interrupted.

  As described above, in the first unit U1, the motor control transistor 113 is maintained in the on state while the ignition switch IG is off. On the other hand, since the control signal is not output from the control circuit 18 to the relay driving transistors 106 and 107 while the ignition switch IG is OFF, the second contact b is closed in each of the relays 108 and 109. As a result, both input terminals of the motor M are grounded via the motor control transistor 113 while the ignition switch IG is off.

That is, in the first unit U1, it becomes possible to execute the motor brake control even during the period when the ignition switch IG is turned off. When the ignition switch IG is turned off, the motor brake control is executed and the window glass WD is removed. It becomes possible to hold stationary. Furthermore, since the first unit U1 does not require the control circuit 18 to be activated constantly or intermittently in executing the motor brake control, it is possible to suppress the power consumption required for executing the motor brake control. Become.
Since the voltage applied to the gate terminal of the motor control transistor 113 during the period when the ignition switch IG is off is almost stable at a magnitude corresponding to the power supply voltage, the control circuit 18 is activated intermittently. Current fluctuations that occur in some cases are suppressed. As a result, it is possible to suppress the occurrence of radio noise due to the current fluctuation when the ignition switch IG is off.

When the ignition switch IG is turned off and the control circuit 18 is not activated, the output of the ENABLE signal toward the amplifier side switch 304 is interrupted, so that the amplifier side switch 304 is turned off. As a result, it is possible to further reduce the power consumption when the ignition switch IG is off.
More specifically, during the period when the ignition switch IG is turned off and the control circuit 18 is in a non-activated state, the low-side transistor 301b of the two bipolar transistors constituting the amplifier 301 is always on. . Here, assuming that the amplifier side switch 304 is not provided, that is, the case where the amplifier 101 shown in FIG. 5 is used in place of the amplifier 301, the anode of the battery B comes out when the ignition switch IG is off. The current flows into the amplifier 301 via the second path BC2, and then goes to the ground via the low-side transistor 301b. When a current (hereinafter referred to as a sneak current) flowing through the apparatus along the above path is generated, the power consumption increases accordingly.

  On the other hand, in the first unit U1, an amplifier-side switch 304 is provided in the amplifier 301 as a switch for cutting off the sneak path, and the switch is turned off while the ignition switch IG is off. I have decided. Thereby, it is possible to suppress the occurrence of a sneak current when the ignition switch IG is turned off, and to further reduce the power consumption when the ignition switch IG is turned off. Specifically, the power consumption when the ignition switch IG is turned off can be suppressed to a level at which leakage occurs from the semiconductor element arranged in the above-described path (path through which the sneak current flows).

  Further, the second path BC2 is provided with a pull-up resistor (that is, the second path-side pull-up resistor 302), and the resistor is constituted by a resistor of 100 kΩ or more. As a result, it is possible to suppress power consumption when the motor control transistor 113 is in the off state during the period when the ignition switch IG is on.

Specifically, when the motor control transistor 113 is in the off state during the period when the ignition switch IG is on, the low-side transistor 301b of the two bipolar transistors constituting the amplifier 301 is in the on state. Become. Therefore, when the motor control transistor 113 is turned off while the ignition switch IG is on, a current flowing from the anode of the battery B to the amplifier 301 via the second path BC2 is inevitably generated. The current passes through the low-side transistor 301b and goes to the ground.
Here, the magnitude (current value) of the current is determined according to the resistance value of the second road-side pull-up resistor 302, and decreases as the resistance value increases. As the current value becomes smaller, it becomes possible to reduce the power consumption when the motor control transistor 113 is in the off state when the ignition switch IG is on.

  Further, in the first unit U1, when the ignition switch IG is turned off and the control circuit 18 is switched from the activated state to the non-activated state, the output of the control signal to the transistor side switch 303 and the amplifier side switch 304 is interrupted. 303 and 304 are automatically switched from on to off. That is, in the first unit U1, a configuration is realized in which the switches 303 and 304 can be appropriately switched on and off according to the state of the control circuit 18.

<< Second configuration example of the control unit >>
A second configuration example of the control unit ECU will be described with reference to FIG. In FIG. 4, the devices with the same reference numerals as those in FIG. 3 are the same as those provided in the present control unit ECU (that is, the first unit U1) according to the first configuration example. Omitted.
This control unit ECU (hereinafter referred to as second unit U2) according to the second configuration example is a so-called H-bridge type motor control device, and as shown in FIG. 4, two relays 108 provided in the first unit U1. , 109, four circuit switching transistors 205, 206, 207, 208 are provided.

More specifically, among the four circuit switching transistors 205, 206, 207, and 208, the first transistor 205 and the third transistor 207 are arranged at the end positions on the downstream side of the high-voltage side line MCh. It consists of a P-type channel power MOSFET. Further, as shown in FIG. 4, the source terminals of the first transistor 205 and the third transistor 207 are connected to each other. The drain terminal of the first transistor 205 is connected to one terminal of the motor M, and the drain terminal of the third transistor 207 is connected to the other terminal of the motor M.
In each of the first transistor 205 and the third transistor 207, discharge resistors 203 and 209 are disposed between the base terminal and the source terminal.

  Further, the gate terminals of the first transistor 205 and the third transistor 207 are connected to the output terminal of the control circuit 18. In other words, each of the first transistor 205 and the third transistor 207 is individually provided with a high-voltage side passage BC10 laid between the gate terminal and the output terminal of the control circuit 18. Thereby, the control voltage from the control circuit 18 can be individually applied to the gate terminals of the first transistor 205 and the third transistor 207. That is, in the second unit U2, each of the first transistor 205 and the third transistor 207 can be individually switched on / off.

  As shown in FIG. 4, gate resistors 201 and 211 and an amplifier 101 are arranged in the middle of each high-voltage side passage BC10. Here, as shown in FIG. 7A, the amplifier 101 arranged in the high-voltage side circuit BC10 is composed of two bipolar transistors connected in series with each other, one of which has a collector terminal of the battery B. An N-type bipolar transistor (hereinafter referred to as a high-side transistor) 101a connected to the anode, and the other is a P-type channel bipolar transistor (hereinafter referred to as a low-side transistor) 101b whose collector terminal is grounded. . In the amplifier 101, the emitter terminal of the high-side transistor 101a and the emitter terminal of the low-side transistor 101b are directly connected to each other.

  On the other hand, among the four circuit switching transistors 205, 206, 207, and 208, the second transistor 206 and the fourth transistor 208 are disposed at the end position on the upstream side of the low-voltage side line MCl, both of which are N-type channels. Power MOSFET. As shown in FIG. 4, the source terminals of the second transistor 206 and the fourth transistor 208 are connected to each other. The drain terminal of the second transistor 206 is connected to the input terminal to which the drain terminal of the first transistor 205 is connected among the input terminals of the motor M, and the drain terminal of the fourth transistor 208 is The third transistor 207 is connected to the input terminal to which the drain terminal is connected.

  In each of the second transistor 206 and the fourth transistor 208, a transistor-side switch 303 and discharge resistors 204 and 210 are disposed between the base terminal and the source terminal.

Similar to the transistor side switch 303 provided in the first unit U1, the transistor side switch 303 is turned on while receiving the ENABLE signal output from the control circuit 18 in the activated state.
The discharge resistors 204 and 210 correspond to first resistors and have a function common to the discharge resistors 111 provided in the first unit U1. The discharge resistors 204 and 210 are arranged in series with the transistor-side switch 303, and more specifically between the gate terminals and the source terminals of the second transistor 206 and the fourth transistor 208, more specifically on the transistor side. The switch 303 is disposed closer to the source terminal.

  Furthermore, the gate terminals of the second transistor 206 and the fourth transistor 208 are connected to the output terminal of the control circuit 18 via the gate resistors 202 and 212. In other words, each of the second transistor 206 and the fourth transistor 208 is individually provided with a low-voltage side path BC11 laid between the gate terminal and the output terminal of the control circuit 18. Here, the low-pressure side passage BC11 corresponds to the first passage BC1 in the first unit U1.

  Since the low voltage side path BC11 is provided for each of the second transistor 206 and the fourth transistor 208, the gate terminal of each of the second transistor 206 and the fourth transistor 208 is supplied from the control circuit 18. Control voltages can be applied individually. That is, in the second unit U2, each of the second transistor 206 and the fourth transistor 208 can be individually switched on / off.

  As shown in FIG. 4, gate resistors 202 and 212 and an amplifier 301 are arranged in the middle of each low-pressure side path BC11. Here, the amplifier 301 arranged in the low-pressure side channel BC11 has the same configuration as the amplification channel 301 provided in the first unit U1, as shown in FIG. 7B. That is, in the amplification path 301 arranged in the low-voltage side path BC11, the N-channel bipolar transistor (that is, the high-side transistor 301a) whose collector terminal is connected to the anode of the battery B, and the collector terminal are grounded. A P-type bipolar transistor (that is, a low-side transistor 301b) is connected in series. As shown in FIG. 7B, an amplifier-side switch 304 is connected to the low-side transistor 301b side. The amplifier side switch 304 is the same as the amplifier side switch 304 provided in the first unit U1, and is turned on only during a period in which the ENABLE signal output from the control circuit 18 is received.

  Further, as shown in FIG. 4, a second path BC2 branched from the high-voltage side line MCh of the motor drive circuit MC is provided at a position located between the gate resistors 201 and 212 and the amplifier 301 in each low-voltage side path BC11. It is connected. In addition, a second road side pull-up resistor 302 having a high resistance (specifically, 100 kΩ or more) is disposed in the middle of the second road BC2.

  On the other hand, in the second unit U2, the control circuit 18 has five output terminals as shown in FIG. Of the output terminals of the control circuit 18, four output terminals are connected to the base terminals of the circuit switching transistors 205, 206, 207 and 208, and are used when a voltage is applied to the base terminals. The remaining one output terminal is used to output an ENABLE signal toward the transistor side switch 303 and the amplifier side switch 304.

In the second unit U2 configured as described above, when the close switch UP or the open switch is operated while the ignition switch IG is ON, the four units described above are selected according to the switch operated. The on / off of the circuit switching transistors 205, 206, 207, 208 is controlled.
That is, when the closed switch UP is operated, the control circuit 18 applies a control voltage to the gate terminals of the first transistor 205 and the fourth transistor 208. Here, the control voltage from the control circuit 18 is amplified by the amplifiers 101 and 301 when applied to the gate terminals of the first transistor 205 and the fourth transistor 208. As a result, the first transistor 205 and the fourth transistor 208 are turned on. As a result, a current flows so as to pass through the first transistor 205 and the fourth transistor 208, so that the motor M rotates normally.

  On the other hand, when the open switch DN is operated, the control circuit 18 applies a control voltage to each gate terminal of the second transistor 206 and the third transistor 207. Here, the control voltage from the control circuit 18 is amplified by the amplifier 101 when applied to the gate terminals of the second transistor 206 and the third transistor 207. As a result, the second transistor 206 and the third transistor 207 are turned on. As a result, a current flows so as to pass through the second transistor 206 and the third transistor 207, and the motor M is reversed.

Similarly to the first unit U1, the second unit U2 can perform PWM control on the rotation speed of the motor M, and the control circuit 18 can control the fourth transistor 208 at a predetermined duty ratio during normal rotation of the motor M. When a control voltage is applied to the gate terminal, the on / off of the fourth transistor 208 is switched at a frequency corresponding to the duty ratio. Thereby, the rotational speed of the motor M at the time of forward rotation is controlled to the speed according to said duty ratio.
Similarly, when the control circuit 18 applies a control voltage to the gate terminal of the second transistor 206 at a predetermined duty ratio during the reversal of the motor M, the on / off state of the second transistor 206 is switched at a frequency corresponding to the duty ratio. become. Thereby, the rotational speed of the motor M at the time of inversion is controlled to a speed according to the duty ratio.

  As described above, the circuit switching transistors (that is, the second transistor 206 and the fourth transistor 208) included in the second unit U2 are the motor control transistor 113 included in the first unit U1, that is, the electric field of the present invention. It corresponds to an effect transistor. The control circuit 18 controls the rotational speed of the motor M by switching on and off these transistors 206 and 208. However, the transistors that are switched on / off for controlling the rotation speed of the motor M are not limited to the low-voltage circuit switching transistors, but are the high-voltage circuit switching transistors (that is, the first transistor 205 and the third transistor). It may be a transistor 207).

  Further, in the second unit U2, similarly to the first unit U1, the motor brake control is executed even during the period when the ignition switch IG is off, that is, during the period when the control circuit 18 is in the non-activated state. It is possible to reliably hold the window glass WD stationary. That is, in the second unit U2, the gate energization of the low-voltage side circuit switching transistors 206 and 208 is maintained during the period when the ignition switch IG is off. As a result, while the ignition switch IG is off, the low-voltage side circuit switching transistors 206 and 208 are maintained in the on state, and both input terminals of the motor M are grounded via the transistors. . As a result, in the second unit U2, it is possible to execute the motor brake control when the ignition switch IG is turned off and reliably hold the window glass WD stationary.

The second unit U2 can execute motor brake control when the ignition switch IG is turned off with smaller power consumption as compared with the conventional H-bridge type motor control device RU2.
Specifically, the second unit U2 has many common points in terms of circuit configuration when compared with the conventional H-bridge type motor control unit RU2 shown in FIG. In FIG. 6, devices having the same reference numerals as those in FIG. 4 are the same as those provided in the present control unit ECU (that is, the second unit U2) according to the second configuration example.

  On the other hand, in the conventional H-bridge type motor control unit RU2, it is difficult to maintain the gate energization of the low-voltage side circuit switching transistors 206 and 208 during the period when the ignition switch IG is off due to its circuit configuration. is there. In order to execute the motor brake control when the ignition switch IG is turned off in the conventional H-bridge type motor control unit RU2, the power supply circuit from the battery B to the control circuit 18 is always energized or intermittently. Is required. However, if the supply of power to the control circuit 18 is executed constantly or intermittently when the ignition switch IG is off, power consumption increases.

  On the other hand, in the second unit U2, when the ignition switch IG is turned off, the control circuit 18 is deactivated, so that application of the control voltage to the gate terminals of the low-voltage side circuit switching transistors 206 and 208 is interrupted. Is done. On the other hand, when the control circuit 18 is deactivated, the output of the ENABLE signal to each of the transistor side switch 303 and the amplifier side switch 304 is interrupted, so that the transistor side switch 303 and the amplifier side switch 304 are turned off. Here, when the transistor-side switch 303 is turned off, the path between the gate terminal and the source terminal is cut off in each of the low-voltage side circuit switching transistors 206 and 208, and charge discharge (gate discharge) through the path is performed. Interrupted.

  By shutting off the above path, the potential of the gate terminal is fixed to the anode potential of the battery B and the potential of the source terminal is fixed to the ground potential in each of the low-voltage side circuit switching transistors 206 and 208. It becomes like this. As a result, a potential difference is generated between the gate terminal and the source terminal. In other words, a voltage (power supply voltage) corresponding to the potential difference is applied to each gate terminal of the circuit switching transistors 206 and 208 on the low voltage side. become. As a result, each of the low-voltage side circuit switching transistors 206 and 208 can be maintained in the ON state even during the period when the application of the control voltage by the control circuit 18 is interrupted because the ignition switch IG is turned off. It becomes possible.

  With the configuration described above, even in the second unit U2, it is possible to reliably hold the window glass WD stationary by executing motor brake control when the ignition switch IG is off. In the second unit U2, compared with the conventional H-bridge type motor control unit RU2, it is not necessary to start the control circuit 18 constantly or intermittently in executing the motor brake control. It is possible to suppress power consumption required for execution of control.

Further, the amplifier side switch 304 is turned off when the control circuit 18 is in a non-activated state, so that while the ignition switch IG is turned off, the anode of the battery B passes through the low-side transistor 301b in the amplifier 301. Therefore, it is possible to reduce the power consumption by suppressing the generation of the sneak current toward the ground.
Further, in the second unit U2, since the high-resistance second road-side pull-up resistor 302 is disposed in the middle of the second road BC2, during the period when the ignition switch IG is on, as in the first unit U1. It is possible to suppress power consumption when the low-voltage circuit switching transistors 206 and 208 are turned off. That is, in the second unit U2, as in the first unit U1, when the low-voltage circuit switching transistors 206 and 208 are turned off when the ignition switch IG is turned on, the current flowing toward the ground in the second path BC2 is reduced. Inevitable. At this time, since the second road-side pull-up resistor 302 disposed in the second path BC2 is a high resistor, the generation of the current can be suppressed and the power consumption can be further suppressed.

<< About other embodiments >>
The embodiments described above are merely examples for facilitating understanding of the present invention, and do not limit the present invention. That is, the present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

  In the above embodiment, the motor control device that controls the motor M for opening and closing the window glass WD for the vehicle has been described. However, the window glass WD is an example of an opening / closing body provided in the vehicle. The motor control device of the invention can also be used when controlling an opening / closing body other than the window glass WD, for example, a motor for opening and closing a door or the like. Furthermore, the motor control device of the present invention can be used for controlling a driven body other than the opening / closing body, for example, a motor for driving a wiper device.

  In the above embodiment, as an example of the voltage output unit that outputs a voltage toward the gate terminal of the field effect transistor, the control circuit 18 including a microcomputer is described. However, the present invention is not limited thereto. The power output unit may be a DSP or a gate array. In the above embodiment, the configuration in which the control circuit 18 and its peripheral interface are separated has been described. However, the present invention is not limited to this. For example, a configuration in which a microcomputer and a peripheral interface are integrated as a system IC. May be.

DESCRIPTION OF SYMBOLS 1 Noise removal capacitor 2 Noise removal inductors 3, 4, 5 Reverse connection prevention diode 6 Pull-down resistance 7, 8 Pull-up resistance 9 Reverse connection prevention diode 10 Instantaneous power supply prevention capacitor 11, 12, 13 Current limiting resistance 14, 15, 16 Pull-down resistor 17 Constant voltage power supply circuit 18 Control circuit 19 PWM ripple noise elimination capacitor 101 Amplifier 101a High side transistor 101b Low side transistor 102, 103 Base resistance 104, 105 Discharge resistor 106, 107 Relay drive transistor 108, 109 Relay 110 Gate Resistor 111 Discharge resistor 112 Free-wheeling diode 113 Motor control transistors 201, 202, 211, 212 Gate resistors 203, 204, 209, 210 Discharge resistor 205 First transistor Switching transistor)
206 Second transistor (circuit switching transistor)
207 Third transistor (circuit switching transistor)
208 Fourth transistor (circuit switching transistor)
301 Amplifier 301a High-side transistor 301b Low-side transistor 302 Second-side pull-up resistor 303 Transistor-side switch 304 Amplifier-side switch B Battery BC1 First-pass, BC2 Second-pass BC10 High-voltage-side, BC11 Low-side-side DR DR Vehicle door DN Open switch ECU This control unit GR Gear H Fuse IG Ignition switch M Motor, MC Motor drive circuit MCh High voltage side line, MCl Low voltage side line PW Power window device Rc Excitation coil RD Rotation detection device RU1 Conventional relay drive type motor control device RU2 Conventional H-bridge type motor control device U1 1st unit, U2 2nd unit UP Closed switch WD Window glass XM Lifting mechanism

Claims (5)

A power supply path laid to supply power from the power supply to the motor;
Of the drain terminal and the source terminal, one terminal is connected to the motor, and the other terminal is connected to the ground.
A control circuit for applying a control voltage to the gate terminal of the field effect transistor when in an activated state;
A first path having one end connected to the control circuit and the other end connected to the gate terminal;
Of the power supply path, a second path branched from a location located between the power source and the motor and connected to the first path;
Arranged between the other terminal and the gate terminal and turned on when the control circuit is in the activated state, and when the control circuit is in a non-activated state where the control voltage is not applied to the gate terminal A switch to turn off,
A first resistor disposed between the other terminal and the gate terminal so as to be arranged in series with the switch;
And a second resistor disposed in the second path. A push-pull type amplifier that amplifies the control voltage is provided in the middle of the first path,
Among the two bipolar transistors connected in series in the push-pull type amplifier, another switch is connected to the bipolar transistor side having a ground terminal grounded to the ground,
2. The motor control device according to claim 1, wherein the other switch is turned on when the control circuit is in the activated state and turned off when the control circuit is in the non-activated state.   The motor control device according to claim 2, wherein a resistance value of the second resistor is 100 kΩ or more. The switch and the other switch are both turned on while receiving a control signal output from the control circuit,
The motor control device according to claim 3, wherein the control circuit interrupts the output of the control signal at the time of switching from the activated state to the non-activated state. The motor is a vehicle motor for opening and closing an opening / closing body provided in the vehicle,
The control circuit is in the activated state when an ignition switch provided in the vehicle is on, and is in the non-activated state when the ignition switch is off,
5. The device according to claim 1, wherein both terminals of the vehicle motor are grounded via the field effect transistor during a period in which the ignition switch is off. Motor control device.

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