JP2019216384A - Vehicular control apparatus - Google Patents

Abstract

To suppress current consumption under a vehicle stopping state and suppress a battery from going dead with a simple and low-cost configuration.SOLUTION: A vehicular control apparatus 100 includes: an internal circuit 101; a communication interface circuit 102 receiving a communication signal S1 and outputting it to the internal circuit 101; a switch circuit 103 receiving a first power supply voltage VB1 from the outside and switching a state of a second power supply voltage VB2 output to the internal circuit according to a switching signal SC; an edge detection circuit 104 detecting a rising edge of a communication signal S1 and outputting a pulse signal SP; and a switching signal generation circuit 105 for outputting a switching signal SC to the switch circuit 103 according to the pulse signal SP.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle control device.

  Vehicle control devices used for automobiles and motorcycles used to be turned on / off by a hardware switch or a mechanical relay. However, in recent years, the number of control devices directly connected to a battery without using a mechanical relay or a switch has been increasing. The number of control devices to be mounted is increasing as the functions of vehicles increase. Controlling the standby current of the control device has become a major issue because there is a risk that the battery will run out due to the consumption current (standby current) of the control device when the vehicle is stopped (ignition switch is OFF). .

  In a conventional control device, as disclosed in JP-A-2006-172502 (Patent Document 1) and JP-A-2014-101107 (Patent Document 2), an ON / OFF switching signal of an ignition switch or a power switch is used. Alternatively, the operation / stop of the control device is determined based on a combination of an ON / OFF switching signal of an ignition switch and a communication signal such as various sensors or CAN communication, and the microcomputer is shifted to a sleep mode and power supply to the control circuit is stopped. That has generally been done.

JP-A-2006-172502 JP 2014-101107 A

  However, these conventional methods require wiring that connects the battery to the control device via the ignition switch, in addition to the wiring that is directly connected to the battery (power supply), which complicates the wiring of the vehicle and hinders cost reduction. Had become.

  There is also a method of transitioning the microcomputer to the sleep mode using only the communication signal. FIG. 4 is a diagram illustrating a configuration example of a control device that causes a microcomputer to transition to a sleep mode only with a communication signal. As shown in FIG. 4, the control device 500 includes an internal circuit 501, a power supply circuit 506, and a communication interface circuit 502. The internal circuit 501 includes a microcomputer and a drive circuit. The power supply circuit 506 is a regulator that stabilizes the voltage of the battery B and outputs an internal power supply voltage. The power supply circuit 506 supplies a stabilized internal power supply voltage to the internal circuit 501 and the communication interface circuit 502.

  In this case, a command to shift to the sleep mode is transmitted from the external ECU 701 to the microcomputer of the internal circuit 501 via the communication interface circuit 502, and the microcomputer shifts to the sleep mode to suppress power consumption. However, since the power supply voltage is always supplied to the microcomputer of the internal circuit 501, the power supply circuit 506, and the communication interface circuit 502, the current consumption can be suppressed, but the effect is limited and insufficient.

  The present invention is intended to solve such a problem, and an object of the present invention is to provide a vehicle control device used for an automobile, a motorcycle, or the like, which suppresses current consumption in a state where the vehicle is stopped and reduces the battery power. It is an object of the present invention to provide a control device that realizes the suppression of the above with a simple and inexpensive configuration.

  A vehicle control device according to an embodiment of the present disclosure includes an internal circuit, an interface circuit that receives an input signal and outputs the signal to an internal circuit, and a switching signal that receives a first power supply voltage from outside and outputs a second power supply voltage to the internal circuit. A switch circuit that switches between an active state and an inactive state in accordance with the input signal, an edge detection circuit that outputs a pulse signal when a rising or falling edge of the input signal is detected, and a switch signal to the switch circuit in response to the pulse signal. And a switching signal generating circuit for outputting. The switching signal generation circuit changes the switching signal when the capacitor charged with the pulse signal and the charging voltage of the capacitor exceed a preset threshold, and the state of the second power supply voltage is changed by the switch circuit. And a signal output unit for changing from an inactive state to an active state.

  Preferably, when the input frequency of the pulse signal is lower than a predetermined frequency, the signal output unit changes the switching signal to change the state of the second power supply voltage from the active state to the inactive state.

  Preferably, the capacitor has a first electrode and a second electrode connected to the ground node. The switching signal generation circuit further includes a diode that receives the pulse signal at the anode and has the cathode connected to the first electrode. The signal output unit includes a resistance element connected between the first electrode and the ground node, and a transistor that changes the switching signal in accordance with the charging voltage of the capacitor.

  Preferably, the input signal is a communication signal transmitted from another control device to an internal circuit. The second power supply voltage is supplied to the interface circuit together with the internal circuit.

  ADVANTAGE OF THE INVENTION According to this invention, current consumption in the state where the vehicle was stopped can be suppressed with a simple and inexpensive structure, and a battery dead can be suppressed.

1 is a circuit diagram illustrating a configuration of a vehicle control device according to a first embodiment. FIG. 6 is a waveform diagram for explaining the operation of the vehicle control apparatus of the first embodiment. FIG. 5 is a circuit diagram showing a configuration of a vehicle control device according to a second embodiment. It is a figure which shows the structural example of the control apparatus which makes a microcomputer change to sleep mode only with a communication signal.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding portions have the same reference characters allotted, and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a circuit diagram showing the configuration of the vehicle control apparatus according to the first embodiment. With reference to FIG. 1, the vehicle control device 100 includes an internal circuit 101, a communication interface circuit 102, a switch circuit 103, an edge detection circuit 104, a switching signal generation circuit 105, a power supply circuit 106, a terminal T1 To T5.

  The communication interface circuit 102 receives the communication signals S1 and S2 and outputs them to the internal circuit 101. The switch circuit 103 receives the first power supply voltage VB1 from the outside, and changes the state of the second power supply voltage VB2 supplied to the internal circuit 101 between an active state (ON) and an inactive state (OFF) according to the switching signal SC. Switch between. The edge detection circuit 104 detects a rising edge of the communication signal S1 and outputs a pulse signal SP. The switching signal generation circuit 105 outputs a switching signal SC to the switch circuit 103 in response to the pulse signal SP. The power supply circuit 106 receives the first power supply voltage VB1 (for example, 12V) via the switch circuit 103, and outputs a stabilized second power supply voltage VB2 (for example, 5V).

  The positive terminal of the battery B is connected to the terminal T1, and the negative terminal of the battery B is connected to the terminal T2. Terminals T3 and T4 receive communication signals S1 and S2 from external ECU 201, respectively. The terminal T5 is a terminal from which the internal circuit 101 outputs a control signal to the control target device 200.

  Switch circuit 103 includes a transistor Q4 and resistors R12 and R13. The transistor Q4 is an N-channel MOS transistor, the source is connected to the terminal T1, and the power supply voltage is supplied from the drain to the power supply circuit 106. Resistor R12 is connected between the source and gate of transistor Q4. Resistor R13 has one end connected to the gate of transistor Q4 and the other end receiving switching signal SC. The transistor Q4 is not limited to an N-channel MOS transistor, but may be a P-channel MOS transistor, a bipolar transistor, an IGBT (Insulated Gate Bipolar Transistor), or another power switching element.

  The edge detection circuit 104 includes transistors Q1 and Q3, resistors R3, R5, R6, and R10, a diode D4, and a capacitor C1.

  Transistor Q1 is a PNP transistor, and transistor Q3 is an NPN transistor. The transistor Q1 has an emitter connected to the terminal T1, and outputs a pulse signal SP from the collector. Resistor R5 is connected between the emitter and base of transistor Q1. The cathode of the diode D4 is connected to the terminal T1, and the anode is connected to the base of the transistor Q1. Capacitor C1 has one electrode connected to the base of transistor Q1 and the other electrode connected to the collector of transistor Q3. Resistor R6 is connected between terminal T1 and the collector of transistor Q3.

  A resistor R3 is connected between the base of the transistor Q3 and a terminal T1 for receiving the communication signal S1. A resistor R10 is connected between the base and emitter of the transistor Q3, and the emitter of the transistor Q3 is connected to the ground node.

  The switching signal generation circuit 105 changes the switching signal SC when the charge voltage of the capacitor C2 exceeds a preset threshold value and the capacitor C2 charged by the pulse signal SP. And a signal output unit 110 for changing the state of the two power supply voltages VB2 from an inactive state to an active state.

  When the frequency of inputting the pulse signal SP is lower than a predetermined frequency, the signal output unit 110 changes the switching signal SC to change the switch circuit 103 from the supply state to the cutoff state.

  Capacitor C2 has a first electrode connected to the ground node, and a second electrode. Switching signal generation circuit 105 further includes a diode D5 that receives pulse signal SP at its anode and has its cathode connected to the second electrode of capacitor C2. Signal output unit 110 includes resistors R14 and R15 connected between the second electrode of capacitor C2 and the ground node, and transistor Q5 that changes switching signal SC in accordance with the charging voltage of capacitor C2.

  The communication signal S1 is a communication signal transmitted from the external ECU 201, which is another control device, to the internal circuit 101. The communication interface circuit 102 outputs a communication signal to the internal circuit 101, and the second power supply voltage VB2 is supplied to the communication interface circuit 102 together with the internal circuit 101.

  FIG. 2 is a waveform chart for explaining the operation of the vehicle control device according to the first embodiment. Referring to FIGS. 1 and 2, when an ignition switch of the vehicle is turned on and external ECU 201 starts operating, communication signals S1 and S2 from the external ECU are input. The communication signals S1 and S2 are digital signals. Digital communication signals can be handled by any communication method such as CAN (Controller Area Network) communication, serial communication, and PWM communication by using the edge detection circuit 104 having a circuit constant corresponding to the communication frequency.

  The edge detection circuit 104 detects a rising edge of the communication signal S1 from the external ECU, and outputs a pulse signal SP. In the edge detection circuit 104, only when the rising edge of the communication signal S1 is detected (t1 to t2, t3 to t4...), The transistor Q1 is turned on and outputs the pulse signal SP. The pulse signal SP charges the capacitor C2 via the diode D5. When the charging voltage VC of the capacitor C2 exceeds a preset threshold value Vth (t6), the transistor Q5 is turned on.

  When the transistor Q5 is turned on, the switching signal SC becomes low level, the gate voltage of the transistor Q4 is reduced, and the first power supply voltage VB1 is supplied to the power supply circuit 106. In response to this, the second power supply voltage VB2 output from the power supply circuit 106 is also activated, and the internal circuit 101 and the communication interface circuit 102 become operable.

  If it is desired to gradually increase the charging voltage VC in consideration of noise countermeasures, a resistor may be inserted in series with the diode D5. In the configuration of FIG. 1, the switching signal SC is switched by the threshold value Vth of the transistor Q5. However, the threshold value may be set by inserting a Zener diode in series with the resistor R14.

  When the communication signal S1 is input, the above operation is performed to supply the second power supply voltage VB2 to the internal circuit 101 to control the control target device 200. When the communication signal S1 is turned OFF, the power supply to the internal circuit 101 is stopped to suppress the power consumption of the vehicle control device 100.

  When the communication signal S1 from the external ECU 201 is stopped, the transistors Q3 and Q1 of the edge detection circuit 104 are always turned off, the charge of the capacitor C2 is discharged through the resistors R14 and R15, and the charge voltage VC is reduced and preset. When the voltage falls below the threshold value Vth (t12), both the transistors Q5 and Q4 are turned off, and the power supply circuit 106, the communication interface circuit 102, and the internal circuit 101 stop operating.

  When the communication signal S1 is input, the above operation is performed to supply a power supply voltage to the power supply circuit 106, the communication interface circuit 102, and the internal circuit 101 to control the control target device. On the other hand, when the communication signal S1 is OFF, power consumption is suppressed by stopping power supply to the power supply circuit 106, the communication interface circuit 102, and the internal circuit 101.

  With such a configuration, the vehicle control device 100 according to the first embodiment can start power supply to the internal circuit only from an external signal without using an ON / OFF switching signal from an ignition switch. It becomes. The supply of power to the internal circuit can be stopped only by turning off the communication signal S1 from the outside. Therefore, the number of terminals and wires of the vehicle control device can be reduced.

  Further, since the start / stop of power supply is switched by detecting the edge of the communication signal S1, when the communication signal line becomes short-to-power (fixed at 12V) or ground-fault (fixed at 0V), power supply is stopped. Accidents due to malfunctions can be prevented.

[Embodiment 2]
Although the rising edge of the communication signal or the like is detected in the first embodiment, the falling edge may be detected.

  FIG. 3 is a circuit diagram illustrating a configuration of the vehicle control device according to the second embodiment. Referring to FIG. 3, vehicle control device 100A receives internal circuit 101, communication interface circuit 102 that receives communication signals S1 and S2 and outputs the same to internal circuit 101, and receives first power supply voltage VB1 from the outside. The switch circuit 103 that switches the state of the second power supply voltage VB2 output to the circuit in response to the switching signal SC, the edge detection circuit 104A that detects the rising edge of the communication signal S1 and outputs the pulse signal SP, and the pulse signal SP Accordingly, a switching signal generation circuit 105 that outputs a switching signal SC to the switch circuit 103 is provided.

  Internal circuit 101, communication interface circuit 102, switch circuit 103, and switching signal generation circuit 105 are the same as those in the first embodiment, and thus detailed description will not be repeated.

  The edge detection circuit 104A includes transistors Q1, Q3, Q6, resistors R3, R5, R6, R10, R16, R17, a diode D4, and a capacitor C1.

  Transistors Q1 and Q6 are PNP transistors, and transistor Q3 is an NPN transistor. The transistor Q1 has an emitter connected to the terminal T1, and outputs a pulse signal SP from the collector. Resistor R5 is connected between the emitter and base of transistor Q1. The cathode of the diode D4 is connected to the terminal T1, and the anode is connected to the base of the transistor Q1. Capacitor C1 has one electrode connected to the base of transistor Q1 and the other electrode connected to the collector of transistor Q3. Resistor R6 is connected between terminal T1 and the collector of transistor Q3.

  A resistor R16 is connected between the terminal T3 that receives the communication signal S1 from the external ECU 201 and the base of the transistor Q6. A resistor R16 is connected between the terminal T1 to which the positive electrode of the battery B is connected and the base of the transistor Q6.

  A resistor R3 is connected between the base of the transistor Q3 and the collector of the transistor Q6. A resistor R10 is connected between the base and emitter of the transistor Q3, and the emitter of the transistor Q3 is connected to the ground node.

  Since the edge detection circuit 104A inverts the polarity of the communication signal S1 by the transistor Q6 and then applies the inverted signal to the base of the transistor Q3, the edge detection circuit 104A detects the fall of the communication signal S1.

  The vehicle control device 100A according to the second embodiment has the same advantages as the vehicle control device 100 according to the first embodiment.

  According to the first and second embodiments described above, by detecting the edge of the communication signal and switching the power supply, the wiring from the ignition switch can be omitted, and the circuit of the control device is simplified. be able to. Thereby, the price reduction of a control apparatus and a harness is realizable.

  In addition, since the edge of the communication signal is detected and the power supply to the power supply circuit, interface circuit, and internal circuit is stopped by the switch circuit, the current consumption is limited to the leakage current of the switch circuit. Sleep mode), the current consumption can be greatly reduced.

  The vehicular control devices described in the first and second embodiments can be applied to all in-vehicle electrical components. For example, it can be applied to EPS (Electric Power Steering), water pump control, and the like. The input signal is exemplified as a communication signal. However, as long as the input signal is a digital signal that is switched between a high level and a low level, the edge of various sensor signals may be detected to control the switch circuit.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  100, 100A vehicle control device, 101, 501 internal circuit, 102 communication interface circuit, 103 switch circuit, 104, 104A edge detection circuit, 105 switching signal generation circuit, 106 power supply circuit, 110 signal output unit, 200 controlled device, B Battery, C1, C2 capacitors, D4, D5 diodes, 201 external ECU, Q1, Q3, Q4, Q5, Q6 transistors, R3, R5, R6, R10, R12, R13, R14, R15, R16 resistors.

Claims (4)

Internal circuitry,
An interface circuit for receiving an input signal and outputting it to the internal circuit;
A switch circuit that receives a first power supply voltage from the outside and switches a state of a second power supply voltage output to the internal circuit between an active state and an inactive state according to a switching signal;
An edge detection circuit that outputs a pulse signal when detecting a rising or falling edge of the input signal;
A switching signal generation circuit that outputs the switching signal to the switch circuit in response to the pulse signal;
The switching signal generation circuit includes:
A capacitor that is charged by the pulse signal;
A signal output unit that changes the switching signal when a charging voltage of the capacitor exceeds a preset threshold value, and changes the state of the second power supply voltage from an inactive state to an active state by the switch circuit; A control apparatus for a vehicle, including:   The signal output unit, when the input frequency of the pulse signal is lower than a predetermined frequency, changes the switching signal to change the state of the second power supply voltage from an active state to an inactive state. Item 2. The vehicle control device according to item 1. The capacitor has a first electrode and a second electrode connected to a ground node;
The switching signal generation circuit includes:
A diode that receives the pulse signal at an anode and has a cathode connected to the first electrode;
The signal output unit is
A resistance element connected between the first electrode and the ground node;
The vehicle control device according to claim 1, further comprising: a transistor that changes the switching signal according to a charging voltage of the capacitor. The input signal is a communication signal transmitted from the other control device to the internal circuit,
The vehicle control device according to claim 1, wherein the second power supply voltage is supplied to the interface circuit together with the internal circuit.

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