Abstract: Provided is a load drive device for controlling a fuel injection device for a vehicle engine and capable of checking an operation of the fuel injection device with high reliability without actually injecting fuel before starting the engine.

Abstract: A high-performance and highly reliable load driving device is provided that can quickly charge an ESD protection capacitor even at the time of load disconnection and complete all diagnoses of the driving system driver within a required time in a load driving device including a diagnosis circuit of a driving system driver and an ESD protection capacitor. A load driving device includes a load; a first switch element connected to the load and configured to control driving of the load; an ESD protection capacitor connected between the load and the first switch element; a charging circuit connected between the load and the first switch element and configured to charge the ESD protection capacitor; and a second switch element connected between the ESD protection capacitor and the charging circuit.

Abstract: A large current flowing when energization by normal load drive control is performed at the time of a load short-circuit is prevented. A load drive device 100 includes drive switches 61 and 62 that turn on or off the current supplied from a power source to a load 70, a switch drive circuit 20 that transmits a drive signal to the drive switches 61 and 62 based on a control command from an arithmetic device 10, and a constant current source 40 that supplies the current to the load 70 without passing through the drive switches 61 and 62. Then, the switch drive circuit 20 performs control so as not to turn on either the drive switches 61 or 62 when the voltage between both ends of the load 70 becomes equal to or less than the determination value in a state where the drive switches 61 and 62 are turned off and in a state where the current is supplied from the constant current source 40 to the load 70.

Abstract: A drive circuit is controlled when power is interrupted. When power is turned off, a main power supply is switched to a sub-power supply, and a residual charge of a step-up circuit is lowered to a drive voltage of a drive circuit using a step-down circuit is used as the sub-power supply.

Abstract: Provided is an injector control unit capable of preventing unintended fuel injection other than an engine drive period. The injector control unit includes a cutoff mechanism for cutting off current supply to the injector from at least the ignition OFF to the next ignition ON.

Abstract: Provided is a load drive device for controlling a fuel injection device for a vehicle engine and capable of checking an operation of the fuel injection device with high reliability without actually injecting fuel before starting the engine.

Abstract: A drive circuit is controlled when power is interrupted. When power is turned off, a main power supply is switched to a sub-power supply, and a residual charge of a step-up circuit is lowered to a drive voltage of a drive circuit using a step-down circuit is used as the sub-power supply.

Abstract: Provided is an injector control unit capable of preventing unintended fuel injection other than an engine drive period. The injector control unit includes a cutoff mechanism for cutting off current supply to the injector from at least the ignition OFF to the next ignition ON.

Abstract: Provided is an electronic control device capable of always achieving a desired injector injection amount by preventing a change in injector opening time regardless of a change (a decrease) of a power supply voltage for opening a valve of an injector. A precharge current amount at the time of precharge control is changed in a stepwise manner based on a voltage of the injector valve open power supply device 10 at the time of the precharge control.

Abstract: An internal combustion engine control device that can ensure diagnosis of whether a fuel injection cut function normally works and that further permits startup of an internal combustion engine in a case in which the fuel injection cut function normally works is provided. To attain the internal combustion engine control system, the startup of the internal combustion engine is prohibited when carrying of a diagnostic monitoring current based on a diagnostic drive signal related to each of fuel injection valves to each of fuel injection valves in a case of transmitting a drive prohibition signal related to each of fuel injection valves to a fuel injection valve drive circuit before the startup of the internal combustion engine and transmitting the diagnostic drive signal related to each of fuel injection valves to the fuel injection valve drive circuit.

Abstract: Provided is a booster device for driving an injector which can suppress an insufficiency of a boost voltage applied to the injector even when the fuel injection interval is short. A boost driver (switching element) is connected to a boost coil in series and turns on/off the conduction of the boost coil. A boost capacitor applies a voltage to the injector. A boost diode has an anode connected to a connection point of the boost coil and the boost driver and a cathode connected to the boost capacitor. A boost gate control circuit controls the boost driver to be turned on/off so as to increase a charging speed of the boost capacitor increases when a decision period indicating a period corresponding to an injection interval of the injector is equal to or less than the first threshold value.

Abstract: Provided is an electronic control device configured to reduce power consumption of a power-supply activation device while maintaining driving of a power supply device. A control unit 18 (the electronic control device) includes an arithmetic device 8, a power supply device 5 which supplies power to the arithmetic device 8, a power-supply activation device 2 which activates the power supply device 5, a power supply maintaining signal line 9 (first signal line), and a reset signal line 11 (second signal line). The power supply maintaining signal line 9 (first signal line) transmits a power supply maintaining signal (power supply drive maintaining signal) for maintaining drive of the power supply device 5, from the arithmetic device 8 to the power supply device 5. The reset signal line 11 (second signal line) transmits a reset signal for resetting the power-supply activation device 2, from the arithmetic device 8 to the power-supply activation device 2.

Abstract: An internal combustion engine control device that can ensure diagnosis of whether a fuel injection cut function normally works and that further permits startup of an internal combustion engine in a case in which the fuel injection cut function normally works is provided. To attain the internal combustion engine control system, the startup of the internal combustion engine is prohibited when carrying of a diagnostic monitoring current based on a diagnostic drive signal related to each of fuel injection valves to each of fuel injection valves in a case of transmitting a drive prohibition signal related to each of fuel injection valves to a fuel injection valve drive circuit before the startup of the internal combustion engine and transmitting the diagnostic drive signal related to each of fuel injection valves to the fuel injection valve drive circuit.

Abstract: Provided is an electronic control device capable of always achieving a desired injector injection amount by preventing a change in injector opening time regardless of a change (a decrease) of a power supply voltage for opening a valve of an injector. A precharge current amount at the time of precharge control is changed in a stepwise manner based on a voltage of the injector valve open power supply device 10 at the time of the precharge control.

Abstract: To protect a switching element to be used in a boost circuit for an in-cylinder injection type internal combustion engine or the like from damage caused by overheating without using a temperature detection element. In a control circuit that switches a switching element between a conductive state and a non-conductive state, the switching element is controlled or a temperature of the switching element is estimated based on a potential difference between an input terminal and an output terminal of the switching element and a voltage applied to a control terminal of the switching element in the conductive state.

Abstract: Provided is an electronic control device configured to reduce power consumption of a power-supply activation device while maintaining driving of a power supply device. A control unit 18 (the electronic control device) includes an arithmetic device 8, a power supply device 5 which supplies power to the arithmetic device 8, a power-supply activation device 2 which activates the power supply device 5, a power supply maintaining signal line 9 (first signal line), and a reset signal line 11 (second signal line). The power supply maintaining signal line 9 (first signal line) transmits a power supply maintaining signal (power supply drive maintaining signal) for maintaining drive of the power supply device 5, from the arithmetic device 8 to the power supply device 5. The reset signal line 11 (second signal line) transmits a reset signal for resetting the power-supply activation device 2, from the arithmetic device 8 to the power-supply activation device 2.

Abstract: To protect a switching element to be used in a boost circuit for an in-cylinder injection type internal combustion engine or the like from damage caused by overheating without using a temperature detection element. In a control circuit that switches a switching element between a conductive state and a non-conductive state, the switching element is controlled or a temperature of the switching element is estimated based on a potential difference between an input terminal and an output terminal of the switching element and a voltage applied to a control terminal of the switching element in the conductive state.

Abstract: In a step-up circuit, which is an electronic control device, changes in current caused by a current rise when stepping up is started and a current drop when stepping up is stopped generate magnetic induction noise due to fluctuations in the electromagnetic induction voltage in signal lines around the step-up circuit. The present invention is a step-up circuit for stepping up by current control, wherein the step-up circuit is provided with a plurality of target current values for retaining a step-up current so that the current is raised in a stepwise manner when stepping up is started and dropped in a stepwise manner when stepping up is stopped. The present invention reduces electromagnetic induction noise generated by the changes in current when stepping up is started and when stepping up is stopped.

Abstract: Provided is a booster device for driving an injector which can suppress an insufficiency of a boost voltage applied to the injector even when the fuel injection interval is short. A boost driver (switching element) is connected to a boost coil in series and turns on/off the conduction of the boost coil. A boost capacitor applies a voltage to the injector. A boost diode has an anode connected to a connection point of the boost coil and the boost driver and a cathode connected to the boost capacitor. A boost gate control circuit controls the boost driver to be turned on/off so as to increase a charging speed of the boost capacitor increases when a decision period indicating a period corresponding to an injection interval of the injector is equal to or less than the first threshold value.

Abstract: In a step-up circuit, which is an electronic control device, changes in current caused by a current rise when stepping up is started and a current drop when stepping up is stopped generate magnetic induction noise due to fluctuations in the electromagnetic induction voltage in signal lines around the step-up circuit. The present invention is a step-up circuit for stepping up by current control, wherein the step-up circuit is provided with a plurality of target current values for retaining a step-up current so that the current is raised in a stepwise manner when stepping up is started and dropped in a stepwise manner when stepping up is stopped. The present invention reduces electromagnetic induction noise generated by the changes in current when stepping up is started and when stepping up is stopped.