JP6731494B2 - Control device - Google Patents

Description

The present invention relates to a control device.

Since it is difficult to start the internal combustion engine of a vehicle independently, there are cases where it is started using a starter, for example. As the starter, for example, a starter provided with an electrically driven starter motor is generally known. Specifically, the starter motor is connected to the power supply via a starter relay configured as a so-called meshing relay. When a drive signal is supplied to the starter relay based on such a configuration, electric power is supplied from the power supply to the starter, and the starter motor is driven to start the internal combustion engine.

Moreover, when controlling various operations of an automobile, there are not a few cases in which a plurality of electronic control units (ECUs) operate in cooperation. For example, when attention is paid to the configuration for starting the internal combustion engine, the ECU for controlling the start of the internal combustion engine receives a control signal from another unit (for example, another ECU) that performs main control. There is a case where the starter is driven by operating as a subordinate.

For example, Patent Document 1 discloses an example of a configuration in which an internal combustion engine is started by controlling the operation of a drive circuit for driving a starter relay by a control unit such as a microcomputer.

JP, 2010-223058, A

On the other hand, if some abnormality occurs in the control unit of the ECU for controlling the start of the internal combustion engine, and it is difficult to operate the control unit, it becomes difficult to drive the starter. Can be assumed. Under such circumstances, it is required to introduce a mechanism for enabling the starter to be driven based on a control signal supplied from another unit even when some abnormality occurs in the control unit of the ECU. ..

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to utilize a control signal supplied from another unit to operate the starter for starting the internal combustion engine. It is an object of the present invention to provide a control device capable of realizing control in a more preferable manner.

In order to solve the above problems, according to one aspect of the present invention, an input terminal (P11) to which a first signal is supplied from another unit, a drive circuit (110), and the input terminal (P11) are used. A diode (D21) connected so that the first signal is supplied toward the input side of the drive circuit (110), and the drive circuit (110) receives the first input signal. A controller is provided that drives a starter relay by providing a second signal to the starter relay (210) based on the signal.

As described above, according to the present invention, there is provided a control device capable of realizing the control of the operation of the starter that starts the internal combustion engine in a more preferable mode based on the control signal supplied from another unit. It

6 is an explanatory diagram for describing an example of a schematic configuration of an ECU according to a comparative example. FIG. 6 is a timing chart showing an example of drive timing of a starter relay when an ECU according to a comparative example is interposed. It is an explanatory view for explaining an example of a schematic configuration of an ECU according to an embodiment of the present invention. FIG. 3 is a block diagram showing an example of a configuration of a high side driver applied in the ECU according to the same embodiment. 6 is a timing chart showing an example of the drive timing of the starter relay when the ECU according to the embodiment is interposed.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, constituent elements having substantially the same functional configuration are designated by the same reference numerals, and a duplicate description will be omitted.

<<1. Introduction >>
First, an example of a configuration of an ECU relating to control of starting an internal combustion engine and an example of control of starting an internal combustion engine in which the ECU intervenes will be respectively described as comparative examples, and then technical issues of the present invention will be summarized To do.

<1.1. ECU according to comparative example>
As an example of a configuration in which a plurality of ECUs operate in cooperation with each other, an ECU for controlling the start of the internal combustion engine is dependent on a control signal from another unit (for example, another ECU) that mainly performs control. There is a configuration in which the starter is driven by operating the above. On the other hand, if some abnormality occurs in the control unit of the ECU for controlling the start of the internal combustion engine, and it is difficult to operate the control unit, it becomes difficult to drive the starter. Can be assumed. Under such circumstances, it is required to introduce a mechanism for enabling the starter to be driven based on a control signal supplied from another unit even when some abnormality occurs in the control unit of the ECU. ..

For example, FIG. 1 is an explanatory diagram for explaining an example of a schematic configuration of an ECU according to a comparative example, and is supplied from another unit even when some abnormality occurs in the control unit of the ECU. An example of a configuration for enabling the starter to be driven based on a control signal is shown.

Specifically, the ECU 500 according to the comparative example controls the supply of electric power from the electric power source (BAT) to the starter (Starter) 230. Specifically, the ECU 500 controls whether or not a drive signal is supplied to the relay coil of a starter relay 210 that is provided so as to be interposed between the power source and the starter 230, thereby the starter relay. The relay contact (switch) of 210 is switched between a conducting state and a non-conducting state. With such a configuration, when the relay contact of the starter relay 210 is controlled to be in the conductive state, power is supplied from the power source to the starter 230. Further, when the relay contact of the starter relay 210 is controlled to be in the non-conductive state, the power supply from the power source to the starter 230 is cut off.

Here, the configuration of the ECU 500 according to the comparative example will be described in more detail. As shown in FIG. 1, ECU 500 includes ECU pins P11 and P12, a CPU 130, and a high side driver 110.

The ECU pin P11 is an input terminal for inputting a control signal from another unit different from the ECU 500 (for example, another ECU) to the ECU 500. As a specific example, an instruction signal (Starter switch signal) related to an instruction to drive the starter 230 supplied from another ECU is input to the ECU pin P11. The potential of the ECU pin P11 is determined by the resistor R11 provided so as to be interposed between the ECU pin P11 and the reference potential (ground) GND.

An input terminal (Digital input) of the CPU 130 is electrically connected to the ECU pin P11 via a resistor R12. The output terminal (Digital output) of the CPU 130 is electrically connected to the input terminal IN of the high side driver 110. The potential of the output terminal of the CPU 130 is determined by the resistor R13 provided so as to be interposed between the output terminal and the reference potential GND.

The output terminal OUT of the high side driver 110 is electrically connected to the ECU pin P12 via the diode D12. The potential of the output terminal of the high side driver 110 is determined by the resistor R14 provided so as to be interposed between the output terminal and the reference potential GND. The diode D12 is connected so that a signal is supplied from the output terminal of the high side driver 110 toward the ECU pin P12. As a result, even if the signal output from the high-side driver 110 is output to the outside of the ECU 500 via the ECU pin P12 and a reverse current is generated from the ECU pin P12 toward the high-side driver 110, the reverse current is generated. It is shielded by the diode D12.

A part of the signal output from the high-side driver 110 is demultiplexed by a splitter or the like, and the demultiplexed signal is input to the feedback terminal (DIAG) of the CPU 130 via the resistor R15. With such a configuration, for example, the CPU 130 can monitor the signal output from the output terminal of the high-side driver 110 and control the supply of the signal to the input terminal of the high-side driver 110 based on the monitoring result. Becomes

The node n11 located between the ECU pin P11 and the resistor R12 and the node n13 located between the diode D12 and the ECU pin P12 are electrically connected via the diode D11. That is, the node n11 and the node n13 are bypassed via the diode D11. The diode D11 is connected so that a signal is supplied from the node n11 to the node n13. With such a configuration, even if a reverse current is generated from the node n13 to the node n11 (that is, from the ECU pin P12 to the ECU pin P11), the reverse current is shielded by the diode D11.

The ECU pin P12 is electrically connected to one terminal of a relay contact of the starter relay 210. The other terminal of the relay contact is connected to a ground point (earth) via a clutch switch (Clutch SW).

As shown in FIG. 1, the ECU 500 may be provided with at least one of the ECU pins P13 and P14.

The ECU pin P13 splits a part of the signal (power) supplied from the power source (BAT) to the starter 230 via the relay contact of the starter relay 210 by a splitter or the like, and inputs the part of the signal to the ECU 500. It is an input terminal for performing (that is, performing feedback). With such a configuration, for example, the CPU 130 can monitor the state of power supply to the starter 230 based on the signal input from the ECU pin P13.

The ECU pin P14 is an input terminal for demultiplexing a part of the signal supplied to the relay coil of the starter relay 210 and inputting (ie, feeding back) the part of the signal to the ECU 500. .. With such a configuration, for example, the CPU 130 can monitor the state of signal supply to the relay coil of the starter relay 210 based on the signal input from the ECU pin P14.

Subsequently, an example of control of the starter relay 210 with the ECU 500 according to the comparative example interposed will be described with reference to FIGS. 1 and 2.

For example, it is assumed that an external ECU supplies an instruction signal (Starter switch signal) related to an instruction to drive the starter 230 to the ECU pin P11, and the clutch switch is controlled to be in the conductive state.

In this case, as shown in FIG. 1, the instruction signal input to the ECU pin P11 is demultiplexed at the node n11. A part of the demultiplexed instruction signal is bypassed toward the node n13 via the diode D11, output from the ECU pin P12 to the outside of the ECU 500, and supplied to the relay coil of the starter relay 210. That is, the drive signal is supplied to the relay coil of the starter relay 210 via the path indicated by reference numeral C11. As a result, at timing t11, the relay contact of the starter relay 210 is controlled to be in the conductive state, and power is supplied from the power source (BAT) to the starter 230, so that the starter 230 is driven.

The other part of the instruction signal demultiplexed at the node n11 is supplied to the CPU 130 via the resistor R12. As a result, the CPU 130 can recognize the instruction regarding the drive of the starter 230 from the external ECU and execute various controls regarding the drive of the starter 230. As a more specific example, the CPU 130 may drive the high side driver 110 by supplying a drive signal to the high side driver 110 based on an instruction from an external ECU. In this case, the drive signal is supplied to the relay coil of the starter relay 210 via the path indicated by reference numeral C12. As a result, the drive signal is supplied from the high-side driver 110 to the relay coil of the starter relay 210, so that it is supplied from the high-side driver 110 even if the internal combustion engine is not started based on the instruction signal from the external ECU. It becomes possible to assist the start of the internal combustion engine based on the drive signal. At this time, the CPU 130 also monitors the driving states of the starter 230 and the starter relay 210 based on the signals fed back to the ECU pins P13 and P14, and drives the high side driver 110 according to the monitoring result. Good.

Here, referring to FIG. 2, in the example shown in FIG. 1, the signal supply timing to the starter 230 via the path C11 and the signal supply from the high side driver 110 to the starter 230 under the control of the CPU 130. The relationship between timing and will be described. FIG. 2 is a timing chart showing an example of drive timing of starter relay 210 when ECU 500 according to the comparative example is interposed. In FIG. 2, the horizontal axis represents time. The timing chart shown in the upper part of FIG. 2 shows the timing of supplying signals from the external ECU to the ECU pin P11. Further, the timing chart shown in the middle stage shows the supply timing of the drive signal output from the high side driver 110 under the control of the CPU 130. Further, the timing chart shown in the lower part shows the supply timing of the signal output from the ECU pin P12 and supplied to the relay coil of the starter relay 210. In other words, the timing chart shown in the lower part shows the timing at which the relay contact of the starter relay 210 switches between the conducting state and the non-conducting state. Note that the relay contact of the starter relay 210 is controlled to be conductive when the level of the signal supplied to the relay coil of the starter relay 210 indicates a high level.

For example, in the example shown in FIG. 2, the instruction signal is supplied from the external ECU to the ECU pin P11 during the period indicated by reference signs t11 to t13. That is, during the period, a part of the instruction signal is supplied to the relay coil of the starter relay 210 from the ECU pin P11 via the path C11, and another part of the instruction signal is supplied to the CPU 130. When the instruction signal is supplied from another ECU, the CPU 130 drives the high side driver 110 before the supply of the instruction signal is stopped. For example, in the example shown in FIG. 2, the supply of the drive signal from the high side driver 110 to the starter relay 210 is started at the timing indicated by reference numeral t12. In the example shown in FIG. 2, the internal combustion engine is started at the timing indicated by reference numeral t14, and the drive signal is supplied from the high-side driver 110 to the starter relay 210 at the timing indicated by reference numeral t15. Has been stopped at.

As described above, the ECU 500 according to the comparative example uses the instruction signal supplied from the external ECU to the ECU pin P11 during the period indicated by the timings t11 to t13 to drive the starter relay 210. Therefore, for example, even when some abnormality occurs in the CPU 130 and it is difficult for the CPU 130 to operate, the internal combustion engine can be started by the instruction signal from the external ECU.

Further, it is difficult for the ECU 500 to control the signal in the portion indicated by reference numeral S101 in FIG. 2, that is, the instruction signal supplied from the external ECU to the ECU pin P11. On the other hand, the internal combustion engine may not start only with the instruction signal supplied from the external ECU. As a more specific example, even if it is possible to start the internal combustion engine only with an instruction signal supplied from an external ECU at room temperature, in a cold region, the internal combustion engine is started only with the instruction signal. It may be assumed that it cannot be completed. On the other hand, in the ECU 500 according to the comparative example, the CPU 130 controls the supply of the drive signal from the high side driver 110 to the starter relay 210 based on the instruction signal supplied from the external ECU to the ECU pin P11. Therefore, for example, as in the example shown in FIG. 2, even if the internal combustion engine cannot be started only with the instruction signal supplied from the external ECU, the internal combustion engine is supplied with the drive signal from the high side driver 110. It is possible to assist the starting of the.

The example of the configuration of the ECU 500 according to the comparative example and the example of control of the starter relay 210 with the ECU 500 interposed have been described above with reference to FIGS. 1 and 2.

<1.2. Technical issues>
Next, as technical problems of the present invention, technical problems in the ECU 500 according to the comparative example described with reference to FIGS. 1 and 2 will be described below.

As described with reference to FIG. 1, in the ECU 500 according to the comparative example, the instruction signal input to the ECU pin P11 is output from the ECU pin P12 to the outside of the ECU 500 via the bypass path provided with the diode D11. To be done. Based on such a configuration, for example, when an instruction signal is supplied from an external ECU to the ECU pin P11 while the ECU pin P12 is ground-shorted due to some failure, the voltage Von corresponding to the potential of the ECU pin P11 is changed. An overcurrent may be applied to the diode D11 and an overcurrent may flow in the diode D11. Therefore, for example, a case where the diode D11 is damaged due to the inflow of the overcurrent can be assumed.

In view of such a situation, it is conceivable to use a high breakdown voltage element as the diode D11 to prevent damage to the diode D11 due to overcurrent. However, the element adopted as the diode D11 tends to have a complicated internal structure and a larger size as it has a higher breakdown voltage. Therefore, for example, if a high withstand voltage element is applied as the diode D11, it becomes difficult to fit the diode D11 in the housing of the existing ECU 500, and eventually the ECU 500 may have to be upsized. On the other hand, since the installation space of the ECU provided inside the vehicle is limited, it is not desirable to increase the size of the device. If a large diode D11 is applied, it is difficult to install the ECU 500 inside the vehicle. The following situation can be assumed. The element used as the diode D11 tends to be more expensive as it has a higher breakdown voltage. Therefore, by applying a high breakdown voltage element as the diode D11, an increase in cost for realizing the ECU 500 can be expected.

In addition, assuming a flow of an overcurrent, a resistor is connected in series to the diode D11 to limit the current flowing through the diode D11. A measure using a small element) may be considered. However, when a resistor is connected in series to the diode D11, a voltage drop occurs due to the resistor, and a control signal supplied via the diode D11 (that is, an instruction signal supplied from another ECU) causes It may be difficult to drive the starter relay 210.

In view of such a situation, the present invention proposes a mechanism that allows an ECU that can use a control signal supplied from another ECU to drive the starter relay 210 to be small and inexpensive.

<<2. Embodiment>>
The technical features of the ECU according to the embodiment of the present invention will be summarized below.

<2.1. ECU configuration>
First, an example of the configuration of the ECU according to the present embodiment will be described with reference to FIG. FIG. 3 is an explanatory diagram for describing an example of a schematic configuration of the ECU according to the present embodiment. As can be seen from a comparison between FIG. 3 and FIG. 1, the ECU 100 according to the present embodiment is different in that a diode D21 is provided instead of the diode D11 and that a resistor R21 may be provided. The ECU 500 is different from the ECU 500 according to the comparative example described with reference to FIG. Therefore, in the present description, an example of the configuration of the ECU 100 according to the present embodiment will be described focusing on a part different from the ECU 500 according to the comparative example described above, and a detailed description of a part substantially similar to the ECU 500 will be omitted. Omit it.

As shown in FIG. 3, the diode D21 is provided so as to electrically connect the node n11 and the node n21 located on the input side of the high side driver 110. That is, the node n11 and the node n21 are bypassed via the diode D21. The diode D21 is connected so that a signal is supplied from the node n11 to the node n21. That is, even if a reverse current is generated from the node n21 toward the node n11, the reverse current is shielded by the diode D21. A resistor R21 may be provided between the node n21 and the input terminal IN of the high side driver 110. The high side driver 110 corresponds to an example of a “driving circuit” that drives the starter relay.

Here, it is assumed that an instruction signal (Starter switch signal) relating to an instruction to drive the starter 230 is supplied from the external ECU to the ECU pin P11, and the clutch switch is controlled to be in the conductive state.

In this case, first, similarly to the ECU 500 according to the comparative example described above, the instruction signal input to the ECU pin P11 is demultiplexed at the node n11. On the other hand, in the ECU 100 according to the present embodiment, a part of the demultiplexed instruction signal is bypassed toward the node n21 via the diode D21 and is input to the input terminal of the high side driver 110 via the resistor R21. Supplied. Then, the high-side driver 110 is driven based on the instruction signal supplied to the input terminal, and the drive signal is supplied from the high-side driver 110 to the relay coil of the starter relay 210 via the diode D12 and the ECU pin P12. That is, the drive signal is supplied to the relay coil of the starter relay 210 via the path indicated by reference numeral C13. As a result, the relay contact of the starter relay 210 is controlled to be in the conductive state, and power is supplied from the power source (BAT) to the starter 230, so that the starter 230 is driven. The instruction signal supplied to the input terminal IN of the high side driver 110 via the diode D21 corresponds to an example of “first signal”. The drive signal supplied from the high-side driver 110 to the starter relay 210 corresponds to an example of the "second signal".

Here, focusing on the path C13, a drive signal supplied from an external ECU, that is, a signal that is difficult to control by the ECU 100 directly flows into the diode D21. On the other hand, in the ECU 100 according to the present embodiment, the resistor R21 is connected in series to the diode D21 as necessary, so that the current flowing through the diode D21 is limited by the resistor R21. Is also possible. As a result, according to the ECU 100 according to the present embodiment, it is possible to use a low breakdown voltage element (that is, an element having a small size) as the diode D21, so that the ECU 100 is prevented from increasing in size, for example. Is possible and the degree of freedom in design is improved. Further, the ECU 100 according to the present embodiment is configured to drive the high side driver 110 based on an instruction signal supplied from an external ECU and drive the starter relay 210 with a drive signal output from the high side driver 110. ing. That is, in the ECU 100 according to this embodiment, it is possible to output a drive signal of a predetermined level from the high side driver 110 regardless of the level of the signal input to the high side driver 110. Therefore, for example, even if a voltage drop occurs due to the resistor R21, if the high-side driver 110 can be driven, the starter relay 210 can be driven regardless of the influence of the voltage drop.

The other part of the instruction signal demultiplexed at the node n11 is supplied to the CPU 130 via the resistor R12. As a result, similarly to the ECU 500 according to the comparative example described above, the CPU 130 can recognize an instruction regarding driving of the starter 230 from an external ECU and execute various controls regarding driving of the starter 230. In this case, the drive signal is supplied to the relay coil of the starter relay 210 via the path indicated by reference numeral C12. The signal supplied to the high-side driver 110 for the CPU 130 to drive the high-side driver 110 corresponds to an example of the “third signal”.

The example of the configuration of the ECU according to the present embodiment has been described above with reference to FIG.

<2.2. High-side driver configuration>
Next, an example of the configuration of the high side driver applied to the ECU according to the present embodiment will be described with reference to FIG. FIG. 4 is a block diagram showing an example of the configuration of the high side driver applied in the ECU according to the present embodiment.

As shown in FIG. 4, the high-side driver 110 according to this embodiment includes an ESD (Electro-Static Discharge) 111, a control unit (Logic) 112, and a charge pump level shifter rectifier 113. A limit for unclamped ind. loads 114, a current limit 115, a gate protection 116, a transistor 117, and a temperature sensor 119. A voltage source 121 and an overvoltage protection unit 122 are included.

The transistor 117 is composed of, for example, a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), and the feedback diode 118 is connected in anti-parallel to form a switching circuit. A power supply voltage (+Vbb) is applied to the drain terminal side of the transistor 117, and the output terminal OUT of the high-side driver 110 is electrically connected to the source terminal side. That is, when a voltage is applied to the gate terminal of the transistor 117 and the transistor 117 becomes conductive, a drive signal corresponding to the power supply voltage (+Vbb) is output from the output terminal OUT to the outside of the high side driver 110. Whether or not the power supply voltage (+Vbb) is applied is selectively controlled by an ignition switch (IGSW). The potential of the output terminal OUT is determined by the load (resistance) indicated by reference numeral 123.

The voltage source 121 is driven based on the power supply voltage (+Vbb), and applies the voltage V _Logic for driving the control unit 112 to the control unit 112. The overvoltage protection unit 122 is provided to protect the voltage source 121 from overvoltage.

The ESD 111 is a structure for protecting the internal circuits and elements of the high side driver 110 from electrostatic discharge. The input signal input to the input terminal IN of the high side driver 110 is input to the control unit 112 via the ESD 111.

The temperature sensor 119 has a configuration for detecting the temperature inside the high-side driver 110. The temperature sensor 119 outputs information indicating the detection result of the temperature to the control unit 112.

The control unit 112 drives the charge pump level shifter rectifying unit 113 located in the subsequent stage according to whether the level of the input signal input from the input terminal IN via the ESD 111 is high or low. As a specific example, the control unit 112 drives the charge pump level shifter rectifying unit 113 by supplying a drive signal to the charge pump level shifter rectifying unit 113 when the level of the input signal is high.

Further, the control unit 112 may control the driving of the charge pump level shifter rectifying unit 113 according to the temperature detection result of the temperature sensor 119. As a specific example, the controller 112 may limit the drive of the charge pump level shifter rectifier 113 when the temperature inside the high-side driver 110 is equal to or higher than a threshold value.

When the drive signal is supplied from the control unit 112, the charge pump level shifter rectification unit 113 boosts the supplied drive signal and supplies the boosted drive signal to the gate terminal of the transistor 117. That is, the drive signal is supplied from the charge pump level shifter rectifier 113 to the gate terminal of the transistor 117, so that the transistor 117 is controlled to be conductive. Note that a gate protection portion 116 is provided on the gate terminal side of the transistor 117 to protect the gate terminal when an abnormality such as a failure occurs.

The unclamped limiter 114 and the current limiter 115 are limiters for limiting the output of the drive signal from the output terminal OUT. Specifically, the unclamped limiting unit 114 operates as a limiter for preventing the occurrence of abnormality due to inductive loads without clamping the output signal. Further, the current limiting unit 115 operates as a limiter for preventing outflow of overcurrent from the output terminal OUT due to a failure of the system on the output terminal OUT side. As a specific example, when a situation in which an overcurrent is output from the output terminal OUT due to damage to the load 123 or the like is detected, the current limiting unit 115 limits the supply of the drive signal to the gate terminal of the transistor 117. To do. As a result, the transistor 117 becomes non-conductive, and the output of the drive signal from the output terminal OUT is cut off.

Further, as described above, the supply of the power supply voltage (+Vbb) to the high side driver 110 is controlled by the ignition switch. Therefore, the high-side driver 110 according to the present embodiment can stop the output of the drive signal from the output terminal OUT by the ignition switch regardless of the input state of the input signal to the input terminal IN. ..

The example of the configuration of the high side driver applied to the ECU according to the present embodiment has been described above with reference to FIG.

<2.3. Control by ECU>
Next, an example of control of the starter relay 210 with the ECU 100 according to the present embodiment interposed will be described with reference to FIGS. 3 and 5. FIG. 5 is a timing chart showing an example of the drive timing of the starter relay 210 when the ECU 100 according to the present embodiment intervenes. In FIG. 5, the horizontal axis represents time. The timing chart shown in the upper part of FIG. 5 shows the timing of supplying signals from the external ECU to the ECU pin P11. Further, the timing chart shown in the middle stage shows the supply timing of the drive signal output from the high side driver 110 under the control of the CPU 130. Further, the timing chart shown in the lower part shows the supply timing of the signal output from the ECU pin P12 and supplied to the relay coil of the starter relay 210.

Note that, in the present description, similarly to the comparative example described with reference to FIG. 2, an instruction signal (Starter switch signal) relating to an instruction to drive the starter 230 is supplied from the external ECU to the ECU pin P11, and the clutch switch is activated. Is controlled to be in a conductive state. Specifically, similarly to the example shown in FIG. 2, the instruction signal is supplied from the external ECU to the ECU pin P11 during the period indicated by reference signs t11 to t13.

As described above, in the ECU 100 according to the present embodiment, a part of the instruction signal input to the ECU pin P11 and branched at the node n11 is input to the high side driver 110 via the diode D21 and the resistor R21. Input to IN. As a result, the high side driver 110 is driven, and the drive signal output from the output terminal OUT of the high side driver 110 is supplied to the relay coil of the starter relay 210. That is, in the ECU 100 according to the present embodiment, the drive signal is supplied to the relay coil of the starter relay 210 via the path C13 during the period indicated by reference signs t11 to t13. As a result, at timing t11, the relay contact of the starter relay 210 is controlled to be in the conductive state, and power is supplied from the power source (BAT) to the starter 230, so that the starter 230 is driven.

Further, similar to the ECU 500 according to the comparative example described with reference to FIG. 2, another part of the instruction signal demultiplexed at the node n11 is supplied to the CPU 130 via the resistor R12. That is, the CPU 130 may drive the high side driver 110 by supplying a drive signal to the high side driver 110 based on an instruction from an external ECU. In this case, the drive signal is supplied to the relay coil of the starter relay 210 via the path indicated by reference numeral C12. For example, in the example shown in FIG. 5, similarly to the example shown in FIG. 2, the drive signal is supplied from the high side driver 110 to the starter relay 210 at the timing indicated by reference numeral t12 based on the control from the CPU 130. Has been started. In the example shown in FIG. 5, the internal combustion engine is started at the timing indicated by reference numeral t14, and the drive signal is supplied from the high side driver 110 to the starter relay 210 at the timing indicated by reference numeral t15. Stopped at.

Here, pay attention to the period from timing t11 to t13. Similar to the example described above with reference to FIG. 2, it is difficult for the ECU 100 to control the signal of the portion indicated by reference numeral S101, that is, the instruction signal supplied from the external ECU to the ECU pin P11. Therefore, in the ECU 500 according to the comparative example, it is difficult for the ECU 500 itself to control the supply of the signal of the portion indicated by reference numeral S103, that is, the supply of the signal to the starter relay 210 in the period from timing t11 to t13. there were.

On the other hand, in the ECU 100 according to the present embodiment, as described above, the high side driver 110 supplies the signal of the portion indicated by the reference numeral S103. Therefore, for example, even when some abnormality such as a failure occurs in the period from timing t11 to timing t13, the supply of the drive signal to the starter relay 210 can be restricted by the various limiters provided in the high side driver 110. Becomes

The example of the control of the starter relay 210, in which the ECU 100 according to the present embodiment is interposed, has been described above with reference to FIGS. 3 and 5.

<<3. Conclusion >>
As described above, the ECU 100 according to the embodiment of the present disclosure includes the ECU pin P11, the high side driver 110, and the diode D21. A control signal (for example, an instruction signal) is supplied to the ECU pin P11 from another unit (for example, another ECU). The diode D21 is connected so that the control signal is supplied from the ECU pin P11 toward the input terminal IN side of the high side driver 110. Further, the high side driver 110 drives the starter relay 210 by supplying a drive signal to the starter relay 210 based on the input control signal. With the above-described configuration, the ECU 100 according to the present embodiment starts the internal combustion engine because the high side driver 110 is driven based on the instruction signal from the external ECU even when the CPU 130 is difficult to operate. It is possible to

Further, the ECU 100 according to the present embodiment can limit the current flowing through the diode D21 by the resistor R21 by configuring the resistor R21 to be connected in series to the diode D21, if necessary. is there. As a result, it becomes possible to use a low breakdown voltage element (that is, an element having a small size) as the diode D21. Therefore, the ECU 100 according to the present embodiment can be realized smaller and cheaper than the ECU 500 according to the comparative example described above, for example. Moreover, since a small diode D21 can be used, the degree of freedom in design is improved.

Further, in the ECU 100 according to the present embodiment, as described above, the high side driver 110 is driven based on the control signal supplied from the external unit, and the starter relay 210 is driven by the drive signal output from the high side driver 110. It is configured to drive. Therefore, in the ECU 100 according to the present embodiment, the resistor R21 is connected in series to the diode D21 so that even if a voltage drop occurs due to the resistor R21, the starter relay is irrespective of the influence of the voltage drop. It is possible to drive 210.

Further, in the ECU 100 according to the present embodiment, even when it is difficult to control the supply of the control signal from the other unit, the drive signal to the starter relay 210 is output by the various limiters provided in the high side driver 110. It is possible to limit the supply of Therefore, according to the ECU 100 of the present embodiment, for example, when a situation in which an overcurrent is output as a drive signal to the starter relay 210 is detected, the supply of the drive signal is restricted by the control of the ECU 100. It becomes possible to do. Further, in the ECU 100 according to the present embodiment, it is possible to stop the output of the drive signal from the high side driver 110 to the starter relay 210 by the ignition switch regardless of the supply status of the control signal from other units. is there.

The preferred embodiments of the present invention have been described above in detail with reference to the accompanying drawings, but the present invention is not limited to these examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

100 ECU
110 high-side driver 112 control unit 113 charge pump level shifter rectification unit 114 unclamped limiting unit 115 current limiting unit 116 gate protection unit 117 transistor 118 feedback diode 119 temperature sensor 121 voltage source 122 overvoltage protection unit 123 load 130 CPU
210 Starter Relay 230 Starter

Claims (6)

An input terminal (P11) to which the first signal is supplied from another unit,
A drive circuit (110),
A diode (D21) connected so that the first signal is supplied from the input terminal (P11) toward the input side of the drive circuit (110);
Between the diode (D21) and the input side of the drive circuit (110), a resistor (R21) for limiting the current flowing through the diode (D21),
Equipped with
The drive circuit (110) drives the starter relay by supplying a second signal to the starter relay (210) based on the input first signal.
Control device. A control unit (130) for supplying a third signal to the input side of the drive circuit (110) via the resistor (R21) based on the first signal;
The drive circuit (110) supplies a second signal to the starter relay (210) based on the input third signal.
The control device according to claim 1 . The drive circuit (110) starts supplying the second signal to the starter relay (210) based on the first signal, and then supplies the second signal based on the third signal. The control device according to claim 2 , which starts the supply. Wherein the control unit (130), based on the second signal output from said driving circuit (110) controls the supply of the third signal to the drive circuit (110), according to claim 2 or 3 The control device according to 1. It said drive circuit (110) includes a limiter (115) for limiting the output of the second signal based on a predetermined condition, the control apparatus according to any one of claims 1-4. Supply of the second signal to the starter relay by the drive circuit (110) is controlled by the ignition switch (IGSW), the control apparatus according to any one of claims 1-5.

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