A fuel injection controller includes a discharge switch that turns ON/OFF energization of a first energization path from a boost power source of a second booster circuit when a second control IC energizes a second solenoid, a first detection element that detects a value that depends on an energization state of the discharge switch, a constant current switch that turns ON/OFF energization of a second energization path from a power source voltage that outputs a lower voltage than a boost power source voltage when the second control IC energizes the second solenoid, a second element that detects a value that depends on an energization state of the constant current switch, and an energization path controller that switches energization to the second solenoid.

An injection control device controls a solenoid in a fuel injection valve. The injection control device includes a transistor on an upstream side of a first power supply path to the solenoid and a transistor on an upstream side of a second power supply path to the solenoid. The injection control device has another transistor with a body diode arranged in parallel at a position on the first power supply path between the first transistor and an upstream terminal of the solenoid. The injection control device also includes a transistor on the downstream side of the first and second power supply paths. A drive controller in the injection control device drives the solenoid to an open position by switching ON the transistor on the downstream side and the transistor on the upstream side of the first power supply path or the transistor on the upstream side of the second power supply path.

An input protection circuit (200) and associated method are disclosed for protecting a circuit input (V.sub.INP) from positive and negative overvoltages at an input voltage (V.sub.IN) with a high-voltage PMOSFET (P1) having a gate, a drain connected across a zener diode (ZD1) to the gate, and a source connected to receive an input voltage; a blocking FET (N1) having a gate connected to a power supply voltage, a drain connected across a zener diode (ZD2) to the power supply voltage, and a source connected to the gate of the high-voltage PMOSFET; a high-voltage NMOSFET (N3) having a gate connected to the power supply voltage, a source providing the protected output voltage and connected across a zener diode (ZD3) to the gate, and a drain connected to a source follower node and a level shifter circuit (214) connected between the drain of the high-voltage PMOSFET and the source follower node.

In view of the foregoing issues, an object of the present invention is to provide a vehicle control device that reduces the constraints of heat generation and charging time of a booster circuit, and decreases favorably the fuel consumption and exhaust emission of an engine. A vehicle control device installed in a vehicle, the device includes: a battery; a high-voltage battery that has a voltage higher than a voltage of the battery; and a fuel injection device that injects fuel into an internal combustion engine, wherein the vehicle control device includes a control unit that determines whether to supply a drive current to the fuel injection device by the battery or supply a drive current to the fuel injection device by the high-voltage battery, and controls the fuel injection device.

A fuel injection controller includes a discharge switch that turns ON/OFF energization of a first energization path from a boost power source of a second booster circuit when a second control IC energizes a second solenoid, a first detection element that detects a value that depends on an energization state of the discharge switch, a constant current switch that turns ON/OFF energization of a second energization path from a power source voltage that outputs a lower voltage than a boost power source voltage when the second control IC energizes the second solenoid, a second element that detects a value that depends on an energization state of the constant current switch, and an energization path controller that switches energization to the second solenoid.

Provided is a control device of a fuel injection device which can stabilize a behavior of a valve even when a voltage of a voltage source varies, and can reduce a deviation of an injection amount. The fuel injection device includes a valve and a coil which generates a magnetic attraction force to attract a movable element which drives the valve. A control device applies a predetermined voltage to the coil on the basis of an injection pulse, causes a drive current to flow to the coil until the drive current reaches a maximum current, drives the valve by attracting the movable element, and injects fuel. The drive current flowing to the coil is lowered from the maximum current before the valve reaches a desired maximum lift position, and a constant voltage lower than a predetermined voltage or 0 V is continuously applied to the coil until the valve reaches the desired maximum lift position.

A fuel injection control device includes an electric controller controlling an opening and closing of an injector by energizing a coil in the injector, and a booster circuit boosting a battery voltage to generate a boost voltage. The electric controller includes a valve-opening control unit applying the boost voltage and then applying the battery voltage to the coil to execute a valve-opening control to generate a required valve-opening force, an open valve maintenance control unit applying the battery voltage to the coil to execute an open valve maintenance control to generate an open valve maintenance force and is smaller the required valve-opening force, after the valve-opening control, and a current correction control unit executing a current correction control to correct a maximum value of a current flowing through the coil when the boost voltage is applied in the valve-opening control, according to a decreasing quantity of the battery voltage.

A device may determine a timing configuration for an ignition system. The device may pulse a driver to apply a set of resonant voltage pulses to the ignition system. The set of resonant voltage pulses may cause a set of increasing peak voltages. At least one peak voltage, of the set of increasing peak voltages, may satisfy a threshold to cause a spark in a spark plug of the ignition system.

A device may determine a timing configuration for an ignition system. The device may pulse a driver to apply a set of resonant voltage pulses to the ignition system. The set of resonant voltage pulses may cause a set of increasing peak voltages. At least one peak voltage, of the set of increasing peak voltages, may satisfy a threshold to cause a spark in a spark plug of the ignition system.

A fuel injection controller includes an increase control portion applying the boost voltage to the coil to increase a coil current to a first target value, and a constant current control portion applying a voltage to the coil to hold the coil current to a second target value. A threshold is an energization time period that is necessary to reach a boundary point between a seat throttle area of a property line and an injection-port throttle area of the property line from an energization start time point. An initial-current applied time period is from the energization start time point that the boost voltage starts to be applied to the coil to a time point that the coil current is decreased to the second target value. The increase control portion controls the coil current such that the initial-current applied time period is less than the threshold.