Abstract: An internal-combustion-engine fuel injection control device which can accurately control a boosted voltage applied to a fuel injection valve during fuel injection and can control a variation in a fuel injection amount without increasing a size or a cost of the fuel injection control device even when a width of a fuel injection driving pulse to drive the fuel injection valve is small is provided. A fuel injection control device includes a boosting operation control unit configured to start a boosting operation at predetermined timing regardless of an amount of a detected voltage when the detected voltage is higher than a threshold voltage for starting boosting and is lower than a threshold voltage for stopping boosting.

Abstract: The invention, while reducing noise, suppresses a load increase in a processor and a delay in drive control. An engine control unit includes a processor, a driving circuit including a switching element to drive a load such as a fuel injector and an ignition device, and a communication circuit that transmits control signals from the processor to the driving circuit via serial communication. The control signals each include a command frame for controlling the driving circuit and a data frame for driving the load. If a predetermined bits in each of the data frames received from the processor at predetermined time intervals are determined to be the same twice in succession, the engine control unit changes a state of a driving signal ‘Drive’ for driving the load and thereby changes an operating state of the switching element.

Abstract: There is provided an internal combustion engine controller that realizes a reduction in maximum current value and current regulation without sacrificing boost performance.

Abstract: An injector drive circuit including: a step-up circuit generating a high voltage from a power supply; a first switching device connected to a path between the step-up circuit and an injector; a second switching device connected to the power supply; a third switching device connected between the injector and the ground; and a control unit operating the first, second and third switching device according to a value of current flowing through the injector; wherein the control unit has a unit turning on and off the second switching device in a period during which it turns on and off the first switching device a plurality of times; wherein the control unit has, as set values to control the current flowing through the injector, a first threshold defining a lower current limit, a second threshold defining an upper current limit and a third threshold, larger than the second threshold.

Abstract: Disclosed is an electromagnetic valve driving circuit capable of reducing a load of a booster circuit. A boost driving FET 202 is connected to a route formed between the booster circuit 100 and a first terminal of an injector 3. A battery-side driving FET 212 and a battery protection diode Db are connected to a route formed between a positive-polarity side of a power supply and the first terminal of the injector 3. A freewheeling diode Df is connected at a first terminal thereof to a portion between the first terminal of the injector 3 and the battery protection diode Db, and at a second terminal thereof to a grounding side of the power supply. An injector downstream-side driving FET 220 is connected to a route formed between the second terminal of the injector 3 and the grounding side of the power supply.

Abstract: In an internal combustion engine controller, a clock trouble determination signal from a clock trouble determining circuit that diagnoses any clock input trouble is transmitted in parallel with an abnormality diagnosis signal outputted from an abnormality diagnosing circuit and causes it to be inputted to a trouble/abnormality signal output circuit, and the trouble/abnormality signal output circuit achieves logical summing to output one line of resultant trouble/abnormality output OR signals to a microprocessor (MP). The MP outputs to the trouble/abnormality signal output circuit a trouble/abnormality confirmation input signal, and makes definite any of an abnormal state, a clock trouble state and a normal state based on the result of switching control of the status level of the pertinent trouble/abnormality output OR signal.

Abstract: According to the present invention, the operation of a diagnostic circuit within a load drive circuit, which has been built into an electronic control device, is checked without modifying the electronic control device or the like. The load drive circuit, which drives a load such as a solenoid using a DC power supply as a power supply, includes a drive circuit and a diagnostic circuit which is independently provided within the drive circuit. Upon input of a drive-stop signal from a control circuit that controls the drive circuit, the operation of at least the drive circuit stops, so that whether the diagnostic circuit, which diagnoses the condition of the load, is normally operating or not is checked in a condition in which the load drive circuit has been built into the electronic control device.

Abstract: The present invention realizes an injector drive circuit capable of providing high output power of a boost convertor while suppressing increases in size and cost thereof. An injector energizing circuit 200 includes an FET 2 which applies a high voltage 100a generated by a boost convertor 100 to an injection valve 20. The boost convertor 100 includes an input side capacitor 103, a boosting FET 105, a boost coil 104, a boost diode 106, and FETs 108 and 109 provided in association with a negative pole of an output side capacitor 107. During a period in which the high voltage 100a is applied to the injection valve 20, a gate signal 108a of the FET 108 is turned ON and a gate signal 109a of the FET 109 is turned OFF. Consequently, the boosting FET 105 performs a switching operation to turn OFF the gate signal 108a of the FET 108 and turn ON the gate signal 109a of the FET 109 during a period for charging into the output side capacitor 107.

Abstract: A layer short-circuit of a switch element such as a FET included in an electromagnetic load circuit is detected to accurately perform a failure diagnosis of the electromagnetic load circuit. A failure diagnosis circuit 101 is provided which detects a layer short-circuit in which a high-side switch element, a low-side switch element, or an electromagnetic load itself short-circuits with a power supply voltage terminal or a ground in a state of having a predetermined impedance to perform a failure diagnosis.

Abstract: An injector drive circuit including: a step-up circuit generating a high voltage from a power supply; a first switching device connected to a path between the step-up circuit and an injector; a second switching device connected to the power supply; a third switching device connected between the injector and the ground; and a control unit operating the first, second and third switching device according to a value of current flowing through the injector; wherein the control unit has a unit turning on and off the second switching device in a period during which it turns on and off the first switching device a plurality of times; wherein the control unit has, as set values to control the current flowing through the injector, a first threshold defining a lower current limit, a second threshold defining an upper current limit and a third threshold, larger than the second threshold.

Abstract: There is a need for improving switching regulator characteristics and providing a stable power supply controller. The power supply controller uses a battery and either or both functions of stepping up and stepping down a battery voltage. The power supply controller includes a means that prevents a ripple voltage from occurring by stopping the up conversion function for a switching operation in connection with a battery during a predetermined period without changing conditions for a conventional switching device or smoothing circuit and fast stabilizes a primary voltage using only the down conversion function.

Abstract: An internal combustion engine controller comprises a current or voltage source for controlling a potential at a diagnosis position in order to ensure a high-precision fault diagnosis, even if the drive cycle of the electromagnetic load (such as a fuel injector), in the internal combustion engine is shorted. Diagnosis timing is optimally set or the number of determinations for averaging is increased in order to ensure high-precision fault diagnosis without being influenced by unexpected disturbance such as noises. In fault diagnosis of a regeneration circuit into a booster circuit, either an input/output voltage or the regeneration current of a driver of the electromagnetic load is detected.

Abstract: An internal combustion engine controller comprises a booster coil connected to a battery and a booster capacitor. A switch element is connected to the booster coil to control the passage of current through the booster coil and an interruption of the current. The booster capacitor accumulates electrical energy generated with an inductance of the booster coil at the time of the interruption of the passage of the current. A booster control circuit carries out control in a constant boost switching cycle so as to pass the current through the booster coil and the switch element until the current reaches a preset switching stop threshold value and then interrupt the current to charge the energy generated with the inductance of the booster coil into the booster capacitor. The booster control circuit is configured to ensure a minimum time period for the booster capacitor-charging of the energy within the boost switching cycle.

Abstract: A load driving and diagnosis system controls the feed and block of a load current flowing into an inductor such as a solenoid. The load driving and diagnosis system holds a counter-electromotive force, which is developed when the load current is blocked, at a voltage higher than a supply voltage so that the load current will decay for a short time. When an overcurrent condition is established in the load driving and diagnosis system because of a short circuit to a power supply, a malfunction of a circuit or destruction thereof may take place. In addition to a voltage holding means that holds a switching circuit output voltage at a predetermined voltage, a voltage holding means having a different predetermined voltage set therein is included. Moreover, a selection switch that switches the predetermined voltages according to a detected overcurrent condition is included.

Abstract: Disclosed is an electromagnetic valve driving circuit capable of reducing a load of a booster circuit. A boost driving FET 202 is connected to a route formed between the booster circuit 100 and a first terminal of an injector 3. A battery-side driving FET 212 and a battery protection diode Db are connected to a route formed between a positive-polarity side of a power supply and the first terminal of the injector 3. A freewheeling diode Df is connected at a first terminal thereof to a portion between the first terminal of the injector 3 and the battery protection diode Db, and at a second terminal thereof to a grounding side of the power supply. An injector downstream-side driving FET 220 is connected to a route formed between the second terminal of the injector 3 and the grounding side of the power supply.

Abstract: The present invention realizes an injector drive circuit capable of providing high output power of a boost convertor while suppressing increases in size and cost thereof. An injector energizing circuit 200 includes an FET 2 which applies a high voltage 100a generated by a boost convertor 100 to an injection valve 20. The boost convertor 100 includes an input side capacitor 103, a boosting FET 105, a boost coil 104, a boost diode 106, and FETs 108 and 109 provided in association with a negative pole of an output side capacitor 107. During a period in which the high voltage 100a is applied to the injection valve 20, a gate signal 108a of the FET 108 is turned ON and a gate signal 109a of the FET 109 is turned OFF. Consequently, the boosting FET 105 performs a switching operation to turn OFF the gate signal 108a of the FET 108 and turn ON the gate signal 109a of the FET 109 during a period for charging into the output side capacitor 107.

Abstract: A control device 10 for an internal combustion engine 80 includes an injector drive circuit 90 that drives an injector 30 that injects fuel and a temperature detection device that at least detects timing when a temperature condition that the temperature of the injector drive circuit 90 exceeds predetermined temperature is satisfied. The control device 10 includes a heat-generation-suppression control means 104 that performs control for suppressing the heat generation of the injector drive circuit 90. The heat-generation-suppression control means 104 selects, on the basis of a driving state of a vehicle, at least one parameter among an electric current applied to the injector, fuel pressure supplied to the injector 30, the number of revolutions of the internal combustion engine, and voltage from a battery to be boosted and performs control for limiting a value of the selected parameter on the basis of the timing.

Abstract: A layer short-circuit of a switch element such as a FET included in an electromagnetic load circuit is detected to accurately perform a failure diagnosis of the electromagnetic load circuit. A failure diagnosis circuit 101 is provided which detects a layer short-circuit in which a high-side switch element, a low-side switch element, or an electromagnetic load itself short-circuits with a power supply voltage terminal or a ground in a state of having a predetermined impedance to perform a failure diagnosis.

Abstract: In an internal combustion engine controller, a clock trouble determination signal from a clock trouble determining circuit that diagnoses any clock input trouble is transmitted in parallel with an abnormality diagnosis signal outputted from an abnormality diagnosing circuit and causes it to be inputted to a trouble/abnormality signal output circuit, and the trouble/abnormality signal output circuit achieves logical summing to output one line of resultant trouble/abnormality output OR signals to a microprocessor (MP). The MP outputs to the trouble/abnormality signal output circuit a trouble/abnormality confirmation input signal, and makes definite any of an abnormal state, a clock trouble state and a normal state based on the result of switching control of the status level of the pertinent trouble/abnormality output OR signal.

Abstract: There is provided an internal combustion engine controller that realizes a reduction in maximum current value and current regulation without sacrificing boost performance.